Frequently Asked Questions

Training & Safety

Do I need a coach?

It is a good idea to make use of a swimming coach. During a crossing like SwimÖresund, it can be decisive with a good open water coach, specialized in sea swimming. Here you can get swimming programs designed for marathon swimming and get help and coaching in this particular area. See ’COACHES’.

Is marathon swimming dangerous?

As a swimmer, you should be aware of the risks and the responsibility connected to marathon swimming. You should never attempt to swim in open water without being aware of the risks connected to your own survival. Thus, marathon swimming requires total dedication.

The main risks associated with marathon swimming include: hypothermia, inadequate training, overconfidence, inexperience, inadequate preparation and lack of understanding of the challenge being undertaken. It is absolutely necessary to train yourself well before committing to marathon swimming. Both physical and mental training are very important.

The responsibility for your safety lies with you. If you are not ready to swim, do not risk your life or health. It is better to wait and make a new plan for your crossing.

Do I need to practice at sea?

It cannot be repeated enough how important it is to swim outdoors. There is a big difference between lying in the comfort of the swimming pool’s square basin, where the water is warm and controlled, and feeling the forces of nature when you are in the sea, where salt water, currents and waves wash over you. In addition, our bodies react and perform differently when exposed to the large temperature differences that are indoors and outdoors. It takes time for the body to get used to the differences.

Should I be able to breathe to both sides when I swim?

It is a good idea to be able to breathe to both sides (bilateral breathing) when swimming. This is especially important when swimming next to an escort boat. This will enable you to lie comfortably on both sides of the escort boat. The escort boat will lay upwind, so that you avoid inhaling the engine’s petrol or diesel fumes. In addition, breathing to both sides can be beneficial in the face of waves, wind or bright sunshine.

Are there any training possibilities while I wait for my crossing?

You have many possibilities to train while you wait as there there are many harbour baths, beaches and swimming pools in the area around Copenhagen. Most places have a life guard. If necessary, ask this person for advice on the local conditions.


How do I pay for an escort boat?

Escort boats on SwimÖresund’s homepage are neither commercially nor financially connected to SwimÖresund, Therefore, you must book a “window” with them. Payment is between you and the escort boat.

What is a (swimming) ”window”?

When you order your escort boat, you will not be assigned a specific day to swim. Which day you swim in your window depends on weather and sea conditions. Therefore, you must be patient, as the weather is the only thing that cannot be changed. Unfortunately, this can also mean that you will be able to swim in the agreed window.

Can I decide when to swim?

It is not always possible to decide for yourself when one’s crossing starts. Here you will have to trust the people in charge on the escort boat. As the Öresund offers many complicated weather and sea conditions, there are many factors to consider. This means that the pilot keeps a close eye on these factors so that you have the greatest chance of success on the crossing.

What does it mean that I have to swim second?

You may find that two or more swimmers have chosen the same escort boat and the same window as you. Therefore, you should make sure what number you are in relation to other swimmers when you make your agreement with the escort boat. Therefore, remember to order your escort boat in good time, so that you can get out first and swim when the weather and sea conditions are most optimal.

Under which conditions will the pilot abort the crossing?

* If your life or other peoples’ lives are in danger

* Unexpected weather and current conditions that make the crossing impossible

* Dangerous position for decent

* Break down or mechanical failure on the boat’s engine

The Crossing

What is the distance of the crossing?

The distance is approx. 20 kilometer, equivalet of 10.83 nautical miles.

Is there a fixed route?

You start your crossing from Bellevue Beach in Denmark and swim towards Lundåkrabukten in Sweden.

Which month is best to swim

Looking back in time, it appears that July and August are the best months for swimming. The average water temperature in these months is 18 °C (64,4°F).

How long will the crossing take?

Calculating an expected swimming time across the Öresund is an almost impossible task. There are several factors that come into play, such as the weather, the current, the waves, your stamina and your swimming speed on the day. A crossing can last anywhere from 5 hours to 14 hours.

Are all swims in daylight?

When the crossing starts depends on the many weather and sea conditions in Öresund. Therefore, the final call will come from your pilot on the escort boat. Therefore, you can swim both in daylight and in the dark.

Do I need my passport?

It is important that you and your companions/crew bring your passports with you on the swim. Everyone must be able to confirm their identity to both Danish and Swedish authorities, as controls on the water may occur. In addition, your identity must be able to be confirmed to SwimÖresund’s observer.

Do I need insurance?

It is the responsibility of the individual swimmer and their companions to insure themselves against the risks that may arise during the crossing on board the boat and in the water.

Do I need support on the escort boat?

Make sure you have at least one person who can travel with you during the given period. It is important that there is at least one support person on the boat during the crossing, regardless of whether you are swimming solo or in a group. If several crossings are swum in a row, there must be at least two support people on the boat. The support person must take care of the swimmer’s well-being, energy intake and other various needs.

How do I get Feeds from escort boat?

There are two well-known methods of energizing the swimmer. In the first method, the support person extends the Feed over the rail with a so-called feeding rod, after which the swimmer swims up next to the escort boat and takes the energy from the feeding rod. In the second method, the support person throws energy bottles on a string out in front of the swimmer, so that the swimmer swims into the string to consume the energy that way.

How long can be spent on feeding intake?

As there can be a lot of current in the Öresund, it is important that your energy intake is as short as possible – preferably within 1 minute. That way, you avoid drifting too far away from the target every time you stop to take in energy.

Do I get a medal when I complete?

An achievement like completing a crossing from Denmark to Sweden deserves a special gesture. Therefore, you will receive a nice certificate issued by SwimÖresund and the World Open Water Swimming Association (WOWSA), at the same time as you will receive a specially designed medal for your great achievement.


Is there a lot of ship traffic in Öresund?

The Öresund is an iconic international waterway, and has had great strategic importance and influence on Northern European history throughout the ages. The narrow strait connects the world’s largest inland sea, the Baltic Sea, with the Kattegat. More than 45,000 merchant ships sail through Öresund every year. To this must be added the many fishing cutters, recreational sailors, speedboats and other vessels. This makes Öresund extremely busy.

How are the current conditions in Öresund?

The currents in the Öresund can be fickle, mischievous and strong at times. This happens because of the enormous water flow, which either has a northbound direction from the Baltic Sea to the Kattegat or southbound from the Kattegat to the Baltic Sea. The tidal differences are small in the region (less than 20 cm), but the tide has a visible effect on the current strength in the Öresund.

Is the salinity in Öresund the same as elsewhere?

An experienced swimmer will be able to feel the difference in the Öresund from a swim in the North Sea, the Atlantic Ocean, the English Channel, the Mediterranean, the Strait of Gibraltar, and many other places in the world. It will probably feel like you have to fight a little more in Öresund. Why? Because the water in most of the Öresund is brought surface water, and contains a salinity of approximately 10-15 ‰, which is a big contrast to the above sea, canals and straits, where the salinity ranges between 32 ‰ and 39 ‰. This has an effect on your body’s buoyancy, as a greater salinity has a greater density (heavier and denser), and can therefore ‘carry’ a heavier weight.

What is the sea temperature?

The sea temperature in Öresund can vary between 0 C° (32 F°) in winter and 22 C° (71.6 F°) in summer. Warmest months are July and August, where you can expect an average sea temperature of 18 C° (64.4 F°). In the colder years, the temperature has been down to about 15 C° (59 F°).

What animals are found in Öresund?

Despite the heavy shipping traffic, Öresund has a particularly healthy and diverse marine life. There are, among other things, bluefin tuna, porpoises, harbor seals and gray seals. Orca flocksand single individuals are not seen very often, but have been visiting inland Danish waters at regular intervals.

In the Öresund there is a large population of porpoises (Phocoena phocoena), which are closely related to dolphins. They grow to about 180 centimeters long and weigh about 100 kg. Guinea pigs often live in groups of between 2 and 10.

The Atlantic tuna (Thunnus thynnus) has returned to the Öresund, having been overfished since the mid-20th century.Tuna can occasionally be seen swimming or jumping at the surface of the sea.

The Lions’s mane jellyfish (Cyanea capillata) is very common in Denmark. It likes to stay in the deeper water layers, where it is cold.

How is the water quality in Öresund?

According to the European Environment Agency (EEA), the bathing water on the Danish and Swedish sides of the SwimÖresund crossing is classified as excellent (2022), which is the highest classification that can be achieved. This classification is given once a year. SwimÖresund does not measure the water quality itself, but Öresund offers numerous marine mammals such as harbor seals, gray seals and porpoises. The latter breed with certainty in Öresund. Which should give an impression of Öresund’s water quality.

Travel & Accommodation

How do I plan my stay in Denmark?

The easiest way to plan your visit to Denmark is to visit VisitCopenhagen. Here you will find practical information, accommodation options, transport, FAQs and much more. It’s all gathered in one place, so you don’t have to surf the internet thinly. The website supports several international languages.

(SwimÖresund has no responsibility or commercial interest in VisitCopenhagen or wishes to promote any particular companies)

What is the total cost?

In addition to the fixed costs, the price depends mainly on your own personal preferences. Therefore, it is impossible to set exact prices, but below is a list of expenses you should take into account when budgetting:

* Registration with SwimÖresund including observer, certificate and specially designed medal

* Escort boat with crew

* Medical certificate

* Return flight from Copenhagen airport

* Sleepover

* Transportation

* Food and drinks

* Other entertainment or experiences while you wait

* Contingencies

Emergency numbers – I need help?

If you need help in emergency situations, you must call 112 to get hold of the police, ambulance or fire brigade. If your inquiry is not urgent, but you need to contact the police – for example due to theft – then you must call (+45) 114. If you are injured or fall ill and need medical attention, you must call (+45) 1813 – This number applies only to the Capital Region (Region Hovedstaden).