The Danube / Donau / Duna River – An Overview

A passage from the North Sea to the Black Sea necessarily involves both the big rivers of Europe, the Rhine and Danube. The Danube is the bigger of the two while the Rhine is the busier. The much smaller and shorter Main river (along with the Altmuhl river) joins the two via the Main-Danube Canal. We made our passage from Duisberg on the German Rhine through to Constanta on the Romanian Black Sea coast. We undertook it as one trip although there are reasons to split it over two seasons. This page covers information pertaining to the Danube river and its ports in the countries it passes through.

With masts down and stored aboard Maringret had the following dimensions:

Air Draft: 3m
Depth: 2m
Length: 18m (due to length of mast)
Water: 400 litres
Diesel: 600 litres

We were satisfied with these dimensions as we figured that we easily fit within the envelope of a commercial barge. So we were comfortable to go anywhere they would. We’re not sure what the maximum dimensions are for the different classes of barges but they were always bigger than us. If there was a choice between a “sportboot” route and the commercial bouyed route we would take the commercial route, confident that we would pass through safely. On the inland waterways the majority of “sportboot” are motorboats with sailing boats being confined to the lakes (or “see” in German). Consequently we were not sure what dimensions were assumed for “sportboot”. All our canal descriptions are based on the assumption of being sufficient for those dimensions to pass through for us with our 2m depth and 3m air draft. Our 18m overall length was never a problem on the canals.

Note: Comments are based on a 2013 passage with very high water levels on the Danube due to extreme rainfall followed by extended drought. Subsequently there were very high levels of siltation in harbours and low water levels on the lower Danube.

Danube River on wikipedia

Terminus Points: Kelheim Germany,  Sulina Romania
Connections to: Danube-Black Sea Canal at Constanta
Locks enroute:
Portion Covered: km 2,408 to km 150
Problems or Issues:

The Danube is a river that is large enough to have a personality. It is the 2nd largest in Europe (after the Volga) and the 30th longest in the world. It is a dynamic river where water levels can literally change over night. When the changes are extreme, as in the late spring of 2013, the damage wreaked can be extensive. The Danube is not a controlled river although certain areas have built bypass canals and now survive by sending the river elsewhere. Over it’s 2,400 km of navigable water much of the route is through empty regions or smaller towns that can not afford to “control” the river. Even when the Danube stays within its banks it is ever changing, channels move, sand bars form, islands appear (and also disappear). At the upper end of the navigable section you are in the marina-boating world of Germany with an Alpine climate; by the lower end you are in the wilds and wilderness of Romania with the climate of the Black Sea.

The sheer scale of the Danube is daunting, it is hard to grasp the extent and range of variety in the river. Some descriptive points are:

  • the navigable Danube can be divided into three equal thirds of 800 km each: the upper third has many cities and much recent history; the middle third has fewer cities and it’s history is generally older; the lowest third has
    very few cities with much wilderness and its history tends to be that of antiquity.
  • the navigable Danube can be divided into two halves of 1,200 km each: the upper half has the cities, history and it’s end is marked by Belgrade which is the last capital and last large city on the river; settlements in the lower half are much smaller, more spread out and contain less of modern historical note although they have some major sites of ancient history.
  • the navigable Danube can also be divided into two parts based on language: from its source to Vienna the river is Germanic; below that it becomes a Slavic river with the final portion in Romania being Latinate.
  • the navigable Danube can be divided into two parts by religion: Vienna marks the furthest point reached by the Muslim Ottoman Empire when it controlled the lower Danube; above Vienna the river remained under German speaking Christian control.
  • the navigable Danube can be divided into two parts based on the width of the river: above the Iron Gates dams it is a quickly running river with a normal width; below the Iron Gates the river spreads out and is sometimes kilometres wide with the current dropping away to nothing.
  • the navigable Danube can be divided into two parts based on depth of water: within marked channels there is usually sufficient water year-round above the Iron Gates dams; there can be insufficient water below the Iron Gates dams.

There are a few options for charts:

Regardless of which charts are used, they will be out of date somewhere on the river – most likely in the lower reaches below the Iron Gates dams. The Belgian paper charts seem to be the highest quality and are revised and released yearly. There are multiple digital charts available, we used Navionics which only showed the river course but not any depths – we were not aware of this when we bought them. Then there is the Haselhurst & Dittman book which basically has the same chart information as our Navionics charts. Given the additional information in the Haselhurst & Dittman book there was not really any added advantage for us in having the Navionics digital charts. Other boats had digital charts from other sources which incorporated depths and channels.

It is worth realising before setting out on the Danube that the water changes its route often. Bouyage can be out of date, and charts of any kind are even more likely to be out of date. Given the options available to yachts with budgets it is best to be prepared for the river and the charts disagreeing. Your main hope being that the bouyage has been updated to reflect the new river situation.


For pilot book we used “Die Donau” by Melanie Haselhurst & Kenneth Dittman, second edition, April 2013, published by Delius Klassing. This publication is a double-edged sword, persons using should be aware of various aspects of the book. We have a detailed description of its strengths and weaknesses here. We will refer to it as “the pilot book” for the rest of the page.

The Danube flooding in the spring of 2013 was some of the worst for decades. Towns such as Passau were under up to 9 metres of water. Most harbours along the Danube were aflood with the river often rising higher than the dikes between the harbours and the river. In addition to the structural damage wreaked by the flood waters, there was the siltation. Harbours often received a metre of silt from the flood waters, some harbours were silted up so high that birds were walking across where boats were normally moored. Some clubs were not in a position to pay for expensive dredging to remedy the problems while others were forced to wait until dredging equipment became available for their “non-essential” work – some clubs were having to wait until the end of the 2013 season before their harbours could be made usable again. One harbour even had the army extracting boats from the harbour (with less than 1 metre of water remaining in the entrance). This renders all the depth figures in the Danube pilot books as suspect as the river deposited silt with out regard to who used the harbour. Even some of the waiting pontoons for the locks were silted up and unusable. Any depth figures we list are after the silting and it should be realised that some harbours may choose to pay for dredging to shallower depths than they had previously. The one class of harbours we found to be least affected were the commercial harbours where the sport boats stayed in the same harbour as the commercial ships.

Given that the information in the pilot book edition of 2013 was largely from 2006 we found the most useful source to be Red Sky at Night (link in the next paragraph) which was from 2011. Admittedly it is the log of one boat making one passage down a river that constantly changes but it was 5 years more current than the pilot book which on the ever changing Danube is a big advantage. Also Red Sky at Night made the passage in July & August and their reports are based on those water levels. In the harbours we used we generally found Red Sky at Night to be more concise than the pilot book – perhaps this is a by product of the 2013 edition being an editorial effort of reader’s comments rather than based on passage notes. Also the pictures on the Red Sky at Night website are more of interest to boats making the trip, pictures of harbours, docks etc. while the pilot book is full of pictures of the tourist sites and scenery – not what you want to see when you are trying to find an unmarked harbour entrance.

The combination of the pilot book and Red Sky at Night was the best we could assemble. We also distilled comments from other websites (listed below) and the (very) few other boats we met that were making the passage.


Like so many other aspects the bouyage on the Danube is a continuously changing tale. At the upper portion near Kelheim everything is marked, sometimes multiple times. By the lower reaches the markers may be kilomtres apart. The bouyage of the Danube has a slight personality change with each new country and as you move down the river the bouyage becomes more sparse and often, absent. Below the Iron Gates it is rare for both sides of a fairway to be bouyed, instead one side will be bouyed and ships are best advised to stay closer to that side. Alternatively signs on shore indicate the deeper side of the fairway and once again it is assumed that ships will adhere to the deeper side.


The Danube is a curvaceous river and often the there is no bouyage to indicate where the deep water lies. The general assumption is that deep water lies on the “outer curve” as indicated in the diagram above.

There are two common methods of bouyage on the lower Danube, traditional red and green buoys or red and green signs on the shore. When looking at the diagrams below remember that the bouyage is backwards in the sense that you are going down the river while the river is bouyed for traffic going up – so you keep red to starboard. As a side note, each country seems to have its own shape for the bouys and also its own shade of green and red paint.


The diagram above is of the same river curves shown before except that bouys have been placed on it. Remembering that red is kept to starboard, a ship would pass between the bank and the green buoy, then pass between the red and green pair of buoys  and finally pass as close to the green buoy as possible while still keeping it to port.


The diagram above is of the same river curves but with shore signage placed on it. Once again remembering that red is kept to starboard, a ship would pass as close to the bank with the green sign and then pass as close to the red sign as possible.

At times the channels on the outer curves are 20 metres deep and are almost that close to the shore while the inner part of the curve may be 500 or even 1,000 metres away. We rarely found the bouyage wrong, more often we found it missing. Whether it was missing in that the river had changed, or the bouyage was washed away during floods or it had never been bouyed we never knew.

It is important to know that there are a few occasions when the channel actually cuts a 90 degree turn and goes across the river before making a second 90 degree turn to continue on the opposite bank. This was almost always signed although only by a single red and green on each side.

The tricky water stretches are basically in Bulgaria between Oriohovo and Russe. One approach is to find a commercial barge and follow them. We learned that when you see a lot of barges anchored in the middle of nowhere on the lower Danube it can mean that a blockage has occurred where a barge has got sideways across the channel and is either trying to get itself off or is waiting assistance to get off. We got to the point where when we saw this we would cut the throttle back, try and see what was ahead and if we could see nothing go over to a moored barge and enquire. When the large barges are using full horsepower to get off the ground it is no place for a sport boat to be caught in. This goes even more for the push boats from the convoys as some of them are generating 5,000 horsepower which moves a lot of water and a yacht auxiliary engine (such as our at 64 HP) is no match for their wash.

All aspects of the Danube are large and bridges are no exception. Due to the river width most bridges are multiple span.


A yellow diamond will indicate the span to pass under, a pair of yellow diamonds indicate that there is no opposing traffic in that span (and will usually be accompanied by a do not enter sign on a different span).


There are a number of hazards to a Danube passage:

  • tour boats, AKA hotel boats, AKA “cabine boot” in German
  • shallow water
  • absent bouyage
  • mosquitos

Probably the most constant hazard we had was the tour boats (referred to as “meat containers” by some). They are inconsiderate, create wakes capable of swamping local boats, monopolise docks and try to intimidate other boats. We checked with the police and apparently there are no restrictions on them in the “river” sections of the Danube, only on the parts which are “canalised”. Twice the police were called when they insisted that we vacate a moorage for them to dock and we refused as it was signed for sport boats. Both times the police came and immediately the tour boats cast off and yelled to the police that we had a problem and they had been trying to help us. In both instances the police told us that this was typical bullying behaviour by these boats. Other boats have written of experiencing behaviour in locks where the tour boats turn their engines on full and direct the flow at the sport boats which are then pinned to the walls of the lock. This happened so many times it could not be a coincidence. It should be noted that although the lock operators spend all their time insisting on life jackets (in Austria only) or proper courtesy flags they do nothing about the bullies of the lock.

Shallow water predominantly occurs in the late season in the lower reaches of the Danube. The less draft required obviously the fewer occurrences of shallow water. There are Pegels along the whole river but translating their readings into water available is not something we ever cracked. In fact when we asked locals they also just shrugged. The more draft required the earlier a passage should be planned. The Iron Gates dams are the last water regulation on the Danube and it is below here that water levels can become a problem. This effects commercial shipping also as the convoys or barges must sometimes break apart and pass single file through the shallow stretch as the width of the deep water also decreases as the over all depth decreases. Other websites list where they found shallow stretches and we have listed what we found on our page on <Bulgaria> as that is where we found most of the shallow water. One oft mentioned strategy for dealing with shallow water is to follow a boat that knows the waters. We tried this but usually the commercial traffic was traveling faster than we could keep up with for long stretches. Also when they are traveling in ballast they required less water than we did.

With the ravages of floods bouyage can and does go missing. As a first timer on the river you will of course not know if there is a missing bouy – the pilot book does not list such things. As part of our informal update of the charts in the book the bouys were drawn in for us.

Mosquitos can be fierce. It was not always clear whether a night at anchorage would be one under attack of the dreaded insects or not. Generally places where there were a breeze blowing were much preferable but when light is falling and you must get off the fairway it is not always at a breezy spot. We found the locally sold mosquito coils quite adequate for cleaning the boat out. It is probably best to either buy them in advance or when you see them as when we were in mosquito stretches of the river we usually couldn’t find them in the local stores.


From Kelheim to Silina the number of boat harbours gradually decreases. Over the whole river boat harbours tend to be shallow so less draft is better. Any boat should be prepared to anchor, especially in the lower reaches of the Danube. The more draft you have the more anchoring you will have to do, with 2 metres draft we anchored many more nights than we were in harbour.  Anchoring in a 4 km stream is different than still or tidal water as there is a constant pressure on the under water portion of the boat which keeps it lying true to its anchor. There were some marinas but they were very few and often shallow. We stayed in marinas at both Saal and Apetin. Boat harbours (or sportboothafens as they are also referred to as) are more frequent in the upper river but usually accompanied by shallow water. The final option is docks and barges: there are not many docks suitable and available for pleasure craft while mooring to barges is an option only when a barge is in the right place and the push boat crew is agreeable (which in our experience was most of the time).

Provisioning – Food and Fuel

Provisioning is something like suitable boat harbours in that it is much more frequent in the upper reaches of the Danube and slowly disappears as you go down. We fuelled in Saal and Apetin, both were marinas, both had fuel docks and both had high fuel turn over meaning you were buying fresh fuel. Food is readily available but changes as you move down the river, the upper reaches have much more in canned goods and long life products which are useful on a boat when you find yourself in the middle of nowhere. The lower reaches had much less of tinned or long life products but much more fresh produce which although excellent to eat is hard to carry onboard. The biggest problem was usually one of finding shore access at a location with sufficient shopping. There were many towns passed that were large enough to have the shopping but had no accessible dock or moorage. We did not ever try leaving the boat unattended at anchor and using the dinghy to go ashore for shopping. One store we depended on was Lidl as they offer much the same fare in each country (excepting Serbia where they do not operate). Regardless of the local language and alphabet we could buy products based on the artwork which was the same as all the other countries. In our harbour list we have marked those close to a Lidl store.

Mast Stepping

This topic really only applies for sailing boats. Boats with self-steping masts don’t have to worry about anything other than bridge heights. Being a ketch we were unable to travel with both the masts dressed so we had spent 2 days undressing the masts and stowing all fittings into the forepeak. Then we could store the two masts side by side on a supporting frame along with the booms etc. In order to re-step the masts we needed the reverse two days in order to secure all the fittings onto the masts in order for them to be stepped. Sloops that travel with their masts full dressed obviously won’t have this requirement. From Rousse onwards we were searching for a harbour where we could find a fixed or mobile crane and have the masts stepped. With the water levels so low the water was so far from the quays that no crane would want to try and lift at that angle. We looked into Rousse, Oltenita, Braila and Galati. All had the same problem with the water being so far from where a mobile crane could position itself. In Galati there is a large ship works which probably could have done the lifting but we could find nowhere where we could set the masts out with fittings and tools and not have security issues. Once again, for a sloop with a direct lift to step the mast the Galati ship works most likely could do the job (other yachts have listed that on their websites). In the end we travelled back up river to Cernodova and then down the Danube-Black Sea canal to Constanta where we stepped the masts at Port Tomis which is the sport boat harbour immediately to the north of the large commercial harbour (you must exit the commercial harbour to reach the sport boat harbour).

Background Information

A trip down the Danube is a trip across the ages, across languages and across cultures. Possibly it is unique in the world with respect to the number and variety of cultures it crosses. In order to get more out of the experience we sought out books on the area. Two we found which were well worth reading were:

  • The Danube – A River Guide by Rod Heikell, 1991, Imray Laurie Norie & Wilson, ISBN 0-85288-147-9
    – a well written background to the river with some pilotage notes from the late 1980s.
  • The Danube: A Cultural History – A Cultural History by Andrew Beattie, 2010, Signal Books Limited, ISBN 978-904955-66-5
    – a well written treatment of the social forces and movements along the river.

Possibly the Heikell book is now out of print, we have had our copy for some years. It is worth searching out as the research is done to his normal excellent level. Much of the navigation has altered, one dam has even been built since it was published, and of course the country of Yugoslavia which he crossed is no more. But in spite of these changes his history still shines through and helps illuminate the lands through which you drift down river. To our surprise we found that a lot of the older people we met on the lower Danube found the pictures in the Heikell’s book a reminiscence for times gone by.

The Beattie book is packed full of history and social history as his focus is on the cultural progressions along the river. The one weak thing about this book is that the pictures are not labelled – this is probably a slip up by the publisher.

We read both the Heikell and Beattie books as we went down the river to keep our orientation to the history and culture through which we were passing. Traveling by boat it is easy to become detached from what is on shore – especially if you are anchoring a lot. These two books were indispensable for keeping us in touch with what had happened ashore. Also many sites of interest do not have shore access for boats and the books help fill in these gaps. We made up a spreadsheet of the sites we would see by km marker and had this list to refer to as we went down river.

We also read through “Danube” by Claudio Magris, 1986 which is translated from the Italian original. It is a very scholarly work which focuses on the literary and artistic aspects of the journey down the river. However it has very little that is specific to a boat trip down the river. We also read two other publishings of trips down the river but found little of use in either of these.

The following websites were of varying use for background information:

When dealing with the Danube travel logs age quickly and so the information in the older websites is less useful simply because the river and facilities have changed more since those trips were recorded.


What We Got Right

  • Research & Background Information
    We were surprised by the few boats we met in that they hadn’t really looked into the Danube much before setting out (one boat was convinced that Italy lay on the Danube as they had confused the Bulgarian and Italian flags). Most seemed to be viewing it as a novel route to the Mediterranean (which we did also) and hadn’t thought much beyond that. The numerous books and articles and websites we had read seemed to stand out in contrast from boats who weren’t even sure which countries they were going to pass through and what to do about a courtesy flag for that country. We got a lot out of our research in terms of understanding and preparedness and would recomend it to anyone undertaking the Danube. We have listed the books we found useful above. Also we have listed the websites that listed specifics relevant to taking a boat down the river, often they had better information than the pilot book.
  • Stowage and Tankage
    As a side effect of a 12 metre boat we had sufficient tankage and stowage. Of course this was balanced off by not being able to get into a lot of harbours to do provisioning more frequently. We filled with fuel in Saal and then again in Apetin. Water we filled in Saal only.
  • Ground Tackle
    There are two reasons to anchor on the Danube – no harbour or mooring available and to take advanatge of the lovely nature. Due to draft issues we were blocked from a lot of harbours and so had to anchor out more often. But the flip side was we experienced a nature filled trip down the Danube. There are stretches on the river, primarily below the Iron Gates, where harbours are not available for every night. Also when the river is blocked you may not be able to get to your designated harbour. For these events a boat must have sufficient ground tackle. Anchoring is easy in the river in that you are facing a constant stream flow and assuming you have a big enough anchor, once it is laid you will lie to it very nicely. No tides in and out, no tidal rising and falling of water levels, no swinging at anchor.
  • Wash-Down Pump
    This was connected mainly for washing the ground tackle as the anchor and chain were raised. It turns out that most (but not all) anchorages on the Danube are sandy and so everything comes up clean. But where the wash-down pump came in handy was on deck showers using river water. With the extreme heat (40 C) we encountered due to our late season passage down the river we came to rely on the wash-down pump to cool down.

What We Didn’t Get Right (What We Would Have Done Different)

  • Journey Over 2 Years
    Our purpose was to move Maringret from the North Sea to the Mediterranean in one season. For someone planning on maximising the trip down the Danube it is advisable to consider making the trip over two seasons. The marina in <Saal on der Doanau> has excellent facilities to either leave the boat over the intervening winter or to launch boats trucked there for launching. We wanted to see the Danube and the Main-Donau Canal and so didn’t consider trucking to Saal. Had we split over 2 seasons then we would have had much more time to deal with the Danube water levels (both high and low), been earlier in the season and thereby avoided much of the low water nightmares, and had more time spend on the trip downriver.
  • The Heat
    Although we had planned to pass down the Danube much earlier in the year, we underestimated the heat. From Passau to the Bulagrian/Romanian border we rarely had any clouds, no rain and temperatures consistently in the upper 30s. This is extremely draining when you are constantly on the water and receiving the heat from above and also reflected from below by the water. We had the cockpit covered but with no wind other than the boat’s progress through the water (about 12 kph) there is not much cooling taking place. See the note above about the wash-down pump.
  • Charts
    We bought Navionics charts which do not have depths on them. They were as static as the chartlets in the pilot book – the one advantage was that the GPS signal would allow the chart plotter to move them automatically as the boat moved. Above the Iron Gates this was not a major problem as the water levels are controlled and shallow regions only happened at harbour mouths. But below the Iron Gates the river is no longer controlled and shallow areas appear everywhere. We have not seen or used electronic charts with depth and so can not say how accurate and helpful they might be. Were we to do it again we would look into getting the Belgian charts for below the Iron Gates – certainly for the Balla and Borcea Arms which the pilot book doesn’t cover
  • Reduced Draft Vessel
    Our purpose was to get Maringret (draft of 2 metres) to the Mediterranean from the North Sea. We didn’t select the vessel for the route but rather a route for the vessel. However for someone who is selecting a vessel for this type of journey everything revolves around draft required. Adequate living space, stowage and tankage and that is all that is needed. Proper anchoring capability is also a desirable in order to enjoy the wilderness enroute.
  • Journey Earlier with Higher Water Levels
    We set out with a schedule to travel down the Danube during the month of June – that was before the catastrophic floodings of May 2013. Instead we ended up making the journey in late July and August and encountering drought condition water levels. There isn’t much we could have done about it. We met a boat coming up the Danube who had been held up for 9 weeks in Novi Sad by the flood waters and their damage. A fortnight after they left Novi Sad we couldn’t get into the harbour due to low water levels.
  • Phone Based Internet
    We only had internet through our mobile phone while in Germany. Searching out facilities on the Danube is complex due to the multiple languages and countries and not having internet access was a real problem. Some of the marinas has internet but a lot didn’t (especially in Germany and Austria). People we would ask in the harbours below Austria would simply tell us to look on the internet and possibly mention a website address. Most locals in these countries seem to have internet access of some form and so the internet cafes are fewer and harder to find. Had we had internet access for the countries after Germany it would have helped to adapt to arising situations.
  • NASA WeatherMan
    We specifically installed a NASA WeatherMan RTTY receiver which is dedicated to receiving the German DWD weather forecasts. We didn’t use it once and finally just switched it off. In its place we used the Android app WindGuru which allowed us to add forecast points through its website ( and then would give us 8 day forecasts in 3 hour intervals for each of those forecast points. We created forecast points every 100 km down the river and as we went through simply deleted the forecast points. This worked very well for the whole river, dependent on getting a WiFi signal. We could check data points ahead or behind us to see what the weather was doing (e.g. is there rain happening up river which would mean rising water levels). Of course the WeatherMan will pay for itself once we are back on the oceans and not near phone signals that WindGuru needs.
  • Dog Repellent
    In Bulgaria and Romania we were told “here dogs are free” which really means that there are large numbers of wild dogs and cats. The cats pose minimal problems but the dogs can become threatening if a dominant dog is present. The portable battery operated dog repellents are listed as producing a high pitch sound that dogs find unpleasant and turn away from. Owners we met said that the devices work on most dogs but not all. Certainly there were times when we could have used it to get through an aggressive pack of dogs as opposed to having to walk away and find an alternative route. The packs can be so bad that in one town the police actually came to chase them away. In another town we had to use a taxi to cross an area outside the train station controlled by dog packs.


Thanks to all the barge crews of the Danube who helped us in numerous ways along the river route – especially Mercur 301, Proconsul, Holograf, Lagger, Filias-13, Mecur 204.


  • Die Donau by Melanie Haselhorst & Kenneth Dittmann – read our suggestions for using this publication <here>.
  • The Danube – A River Guide by Rod Heikell, 1991, Imray Laurie Norie & Wilson, ISBN 0-85288-147-9
    – a well written background to the river with some pilotage notes from the late 1980s.
  • The Danube: A Cultural History – A Cultural History by Andrew Beattie, 2010, Signal Books Limited, ISBN 978-904955-66-5
    – a well written treatment of the social forces and movements along the river.
  • we have collected the links we found for the canals and rivers of Germany, eastern France and the Donau
  • some of our sources were online facilities which we list in Android for Sailing

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