Welcome To
Leinster Open Sea
Tell Me More

Welcome to Leinster Open Sea

We are a not for profit organisation working with swimming clubs to establish a summer season of open sea races in a variety of locations along the Leinster coast. We cater for all ages and abilities from teenagers to senior citizens and from novice swimmers to former internationals.

So if you like a challenge, keeping fit and enjoy meeting people of all levels of swimming ability – we’d love to have you join us on one of our many sea swims during the summer months.

For current news, check out our Facebook, Twitter or YouTube pages


Download the Leinster Open Sea race calendar as PDF and the Leinster Open Sea Rules and Swimmers Declaration here

For current news, check out our Facebook, Twitter or YouTube pages

Information for First Time Swimmers

Welcome to Leinster Open Sea Swimming. This page is intended to answer all your questions around participating in Leinster Open Sea races. For you convenience, we have grouped the information into the following categories. Should you still have questions after reading, please contact us.

Before you come to your first Leinster Open Sea race,

  • you should join a swimming club, and
  • you must read the Leinster Open Sea Rules 2018 Rules and Swimmers’ Declaration and consent to these rules by completing the Online Rules and Swimmers’ Declaration

Leinster Swimmers must be a member of a swimming club affiliated with Swim Ireland (or an equivalent overseas governing body) to be able to participate in Leinster Open Sea races. See information about joining a swimming club.

  • General Information
  • About Leinster Open Sea Races
  • Race Distances
  • Participating in Leinster Open Sea Races
  • Registration Fees and Race Entry Fees
  • Major Races
  • Safety
  • Swimming Club Membership
  • Overseas Swimmers
  • Swimmers Under 18 Years of Age (Minors)
  • Wetsuits

General Information

Q: Who are you?

A: Leinster Open Sea is a not for profit voluntary organisation. We work with swimming clubs to establish a summer season of open sea races in a variety of locations along the Leinster.

Q: How can I contact you?

A: You can use our contact form to send us a message. Or email us at leinsteropenseaswim@gmail.com. Or post to our Facebook page. Please provide your mobile phone number, it helps us to get back to you faster because it is easier for us to call you than to reply via email. We try to reply to all queries within a few days.

Q: Where can I find Leinster Open Sea’s rules?

A: You can download the Leinster Open Sea Rules from our Downloads page.

Q: Are newcomers welcome?

A: Absolutely! All sea swimming clubs welcome newcomers to the sport of sea swimming and will help new swimmers on their journey from learning to swim to completing their first open sea race.

Q: What are the benefits of open sea swimming?

  • It’s a challenge to successfully complete an open sea race.
  • Use it as part of a new or complement an existing fitness regime.
  • It’s a great opportunity to socialise and meet with like minded swimmers of all abilities.
  • Open Sea Swimming is a sport which adults can take up even if they have never competed before
  • Open Sea Swimming caters for all ages and levels of ability
  • Complete six sea races (Leinster Swimmers) (4 Ulster, Connacht or Munster) and you can qualify for the major races – Dublin City

Liffey Swim and Dún Laoghaire Harbour Race.

Q: Do you have a race calendar?

A: Yes! Our race calendar provides details about all races nearly every Saturday, Sunday and Bank Holiday during the summer season.

Q: What do I have to do prior to competing in the Leinster open sea races?

A: You must

  • Read and complete the Rules and Swimmer’s Declaration form.
  • Register with a swimming club to get a competitor number.

About Leinster Open Sea Races

Q: When is the Leinster open sea swim season?

A: Our races are typically held around Leinster from June to September each year.

Q: Are there separate races for men and women?

A: At every organised race event there is both a men’s race and a ladies’ race. The ladies’ race starts roughly 1 hour after the men’s race start time.

Q: What is handicapping? How does it work?

A: All swimmers are issued with a handicap start time by the handicapper before each race. Slower swimmers start first, followed by faster swimmers. The handicap ensures weaker and stronger swimmers are equally likely to get a good finish position.

Q: Who sets the handicaps? How is my handicap determined?

A: Your handicap is based on your declared or previous swim time and performance. It will be continually adjusted as you compete in more swims. New swimmers should declare their swim times for set distances like 400m – 800m – and 1200m in a 25m pool so the handicapper can issue you a competitive handicap.

Q: Race start

A: Each race will be started by the handicapper or race starter. The handicap times will be called out by the handicapper and each swimmer should start swimming from the start line when their handicap time is called.

Q: How do I know the race course?

A: The race course will be clearly marked by a number of buoys and will be described by race officials at the race briefing at the start of each race (15 minutes before the start).

Q: What happens at the race finish?

A: The finish will involve swimming up to the race official standing in the water and handing out place cards with the finish positions. You then make sure your name, finish position, and club are recorded by a race official.

Q: Is there a cut of time?

As far as possible we try and let swimmers complete the course in their own time. If a slow swimmer is delaying the start of the next race, because of the importance of catching the tide we have to enforce a cut off time. Clubs will announce cut off times before each race. If you are asked to retire from the race please do so and do not argue with the race officials or rescue crews.

Generally there is between forty five minutes to an hour between the start of men’s races and ladies’ races. On a calm day in slack water, a swimmer in training who holds 2 minutes for 100 metres should complete a course of 1,600 metres in 32 minutes. A slower swimmer who holds 2 minutes 30 for 100 metres should complete a course of 1,600 minutes in 40 minutes. So there is a generous time period in which to complete a 1,600 to 2,000 metre course.

Race Distances

Q: How long are the races?

A: Most races are approximately 1,500 to 1,600 metres. The first race of the season is normally shortened to approximately 1,200 metres so as to allow for swimmers who are returning to the sea to acclimatize.

The following swims are greater than 1,600 metres but no more than 2 kilometres:

  • Island Swim
  • Eddie Herron
  • Corrib
  • Phoenix
  • Wicklow Open

Major race distances:

  • Lough Dan: 10 kilometres and 5 kilometres (fresh water)
  • Dublin City Liffey Swim: approximately 2,200 metres
  • Dún Laoghaire Harbour Race: approximately 2,200 metres

Except for the major races, these are general guidelines and race lengths may vary on the day of the race. Clubs may change the length of the course on the day of the race to accommodate weather and sea conditions. Also, buoys, even if they are well anchored, can move during the course of the race.

Q: How difficult are the races?

A: When trying to assess a race course the distance is only one of many factors which will determine the difficulty or ease of completing the course. Other factors to take into account are: shape of the course, location of the course, weather and wind, water temperature, fresh water vs. salt water, and tidal streams.

For races held in the open sea, the strength and direction of the tide is a more important factor in determining the difficulty or ease of competing than the distance of the race. Therefore to judge or grade an open sea race based on the distance of the race on its own is misleading.

See our page about race conditions and how tides affect swimming in the open sea for more information.

Participating in Leinster Open Sea Races

Q: Can I just turn up at a race event?

A: Yes, you are most welcome. We are all friendly people.

Q: How long before the race do I have to arrive?

A: For your first race you should arrive at least 1 hr before the race time stated on the race calendar. This ensures you have time to register for the race, get your handicap from the race official, view the swim race course, understand the start and finish locations, get dressed – and for some people, settle the nerves.

Q: Do I have to register for a race?

A: Yes. You must register with the handicapper. Registration is usually open from 1 hour until 15 minutes before the race start. Watch out for the queue. When it’s your turn, you pay the registration fee and the handicapper will tell you your handicap. If this is your first Leinster Open Sea race, introduce yourself to the handicapper. If you are a regular competitor, the handicapper will know you already.

Q: Do you accept cards/checks?

A: No. Please pay cash.

Q: Is there a minimum or maximum age to compete in sea swims?

A: No. The majority of members of sea swimming clubs are adults ranging in age from mid-twenties up to post retirement age.

Q: Who can I ask if I have a question?

A: Our race officials are happy to answer your questions. Don’t be shy.

Registration Fees and Race Entry Fees

Q: How much does it cost to register with Swim Ireland?

A: A registration number with Swim Ireland costs €39. If you register after the 13th July registration costs €13. By joining a club you are automatically registered with Swim Ireland. Annual club membership fees vary between 40 and sixty euros for adults.

Q: How much does it cost to participate in a sea race?

A: Entry fees into most of the regular Leinster Open Sea races (except major races) are currently €10 for adults and €5 for minors.

Adult entry fees into the major swims like Dublin City Liffey Swim, Dún Laoghaire Harbour Race and the Lough Dan races are currently €35 for early registration or €60 for late registration and €20 for minors. See the Major Swims page for further details.

Major Races

Q: What are major races?

A: There are four major races: Dublin City Liffey Swim, Dún Laoghaire Harbour Race, Lough Dan 5k/10k/2.5k and The Island Race (from Ireland’s Eye to Howth). You must qualify to compete in these races (see below), and there are special entry forms. Leinster Open Sea will publish the entry forms on this site. Leinster will also have online entries for the Dublin City Liffey Swim and the Dún Laoghaire Harbour Race.

Q: How do I qualify for the Dublin City Liffey Swim or Dún Laoghaire Harbour Race?

A: Swimmers who want to compete in the Dublin City Liffey Swim or Dún Laoghaire Harbour Race must have competed in at least 6 qualifying swims as part of the Leinster Open Sea calendar. Other swims outside of the Leinster Open Sea calendar may be counted as qualifier swims and this will be decided by the Leinster Open Sea by application on an annual basis. See Confined Races entry forms.

Q: Qualification for swimmers from outside Leinster

A: Swimmers from outside Leinster who wish to compete in the Dublin City Liffey Swim or the Dún Laoghaire Harbour Race must show they have completed 4 qualifying swims in Ireland. These swims do not have to be on the Leinster Open Sea calendar, they can be races of approximately 1,600 metres run by any reputable club or organisation. See Ulster, Connacht & Munster Swimmers entry forms.

Q: Qualification for overseas swimmers

A: Swimmers from outside Ireland who wish to compete in the Dublin City Liffey Swim or the Dún Laoghaire Harbour Race must show they are competent swimmers who would be able to complete the course. See Overseas Swimmers entry forms.


Q: Are the races safe?

A: Safety is our number one priority. The safety officer at each race will determine if weather and water conditions are safe enough to start a race. Every sea race is monitored by a safety boat crew from Dublin Civil Defence, paid for by Leinster Open Sea. But it is also up to you as the swimmer to ensure you are adequately prepared to swim in each race. If you are feeling unwell or not confident about completing the course please do not register to swim.

Q: What should I do if I get in trouble while swimming, or if I feel very cold?

A: If you find yourself in difficulties during a race, or very cold, do not continue. Raise your hand and a Civil Defence boat will travel over to you and take you back to shore. Remember, your life is a lot more important than a sea swim! Educate yourself and do not push beyond your limits in this regard.

Q: What is hypothermia? What are its symptoms

A: One of the most serious dangers of sea swimming is hypothermia. It is important to educate yourself on its symptoms before trying your first sea swim. The symptoms and signs of the onset of hypothermia can be difficult to recognise if not self-aware. These symptoms typically include: bouts of shivering, disorientation, irrational behaviour, blueness of the lips, inability to concentrate or co-ordinate speech, and inability to respond to simple requests or questions.

Q: How do I know that I’m ready to swim a race

A: You should acquaint yourself to open sea swimming before coming for your first Leinster sea swim. As race season normally starts in early June, you should be testing your ability to swim in the sea prior to this. Most sea swimming clubs have informal training in the sea just before and during the summer.

Swimmers should be comfortable to be immersed in the sea for at least half an hour. As a guideline, swimmers should be aiming to complete 64 lengths of a 25m pool in under 50mins before they take on the challenge of a 1 mile sea race. Please be safe; always swim with a group and stay near the shoreline. Your first open sea race should not be the first time you swim in the sea.

Also check out our information about race conditions and how tides affect your swimming in the open sea.

Swimming Club Membership

Q: Why should a I join a swimming club

A: By registering with a club, you will be joining up with a group of people who are already involved in sea swimming. They will help orientate and prepare you for your first open sea races.

Q: Do you have a list of swimming clubs

A: The Leinster Open Sea website has a list of masters swimming clubs in the Leinster region.

Q: Do you know a swimming club in my locality

A: Check out our swimming clubs page to see the swim clubs in your locality.

Q: Do I have to train with the club that I join

A: No. You can join any swim club of your choice and are under no obligation to train with that club. Once you are registered with one sea swimming club and have a competitor registration number, you can train with other clubs if you so choose. None of the sea swimming clubs in Leinster prohibit their members from training with other clubs. Sea Swimming is different to other sports in that it is widely accepted that swimmers often train with one or two different clubs, in order to participate in training sessions at convenient times and locations. Most swimming and masters clubs welcome swimmers from other clubs as it helps to keep pool hire costs down.

All clubs have organised indoor pool sessions, which if you so choose, you will be able to participate in and prepare for you first swim. However, many swimmers train on their own because of work and time commitments and may be unable to participate in any club training sessions. That is widely accepted within the sea swimming community. It is entirely up to you, how much training you choose to do with your club or any other club.

Q: Can you help me connect and register with a swimming club

A: Leinster Open Sea can help you connect and register with your chosen swimming club. Please contact us if you need help finding and registering with a masters’ swimming club. We will direct you and introduce you to your nearest sea swimming or masters swimming club.

Registration usually takes two working days after which you will receive a registration number. The registration number entitles you to enter all the Leinster Open Sea races and other open sea races around Ireland. It also allows you to participate in training sessions with your own club or other clubs.

Q: How much does it cost to join a swimming club

A: Most sea swimming clubs operate a pay as you go. They will ask you for an annual registration fee of around 40 to 50 Euro (so as to register you with Swim Ireland) and then they will charge you a couple of Euro for participating in their indoor pool training sessions.

Overseas Swimmers

Q: I’m from overseas. Can I compete in Leinster Open Sea races

A: Swimmers from overseas are welcome to compete in the Leinster Open Sea races. Swimmers from overseas must be registered with a FINA affiliated national governing body in their home country. Please scan and email your membership card to leinsteropenseaswim@gmail.com. If you are not registered in your home country we are happy to arrange registration here in Ireland.

Swimmers Under 18 Years of Age (Minors)

Q: I’m under 18. Can I compete in Leinster Open Sea races

A: Parents or guardians of children under eighteen years of age must sign the consent form on the Rules and Disclaimer form. Swimmers under eighteen years of age must be registered with a swimming club.


Q: Can I wear a wetsuit

A: In general, swimmers are not permitted to use or wear any device or swimsuit that may aid their speed, buoyancy, heat retention or endurance (such as wetsuit, webbed gloves, paddles, fins, etc.). Swimsuits may not be made from neoprene or any other material which offers similar heat retention properties (as determined by the handicapper and the race team). If in doubt, arrive early for registration and ask the handicapper and their team.

Mostly all (99%) swimmers who swim in the Leinster Open Sea races do not wear wetsuits. However, Leinster Open Sea appreciates that for some new swimmers who are coming from either a wetsuit background or who have never swam in the Irish Sea before may wish to swim a couple of races with a wetsuit to help them orientate and acclimatise.

Swimmers who choose to wear a wetsuit will not be part of the competition and races in wetsuits do not count as qualifiers for the Dublin City Liffey Swim or the Dún Laoghaire Harbour Race.

Q: Are there exceptions to the wetsuit rule

A: At the discretion of the Handicapper and Leinster Open Sea, swimmers who suffer from a medical condition and who are instructed to wear wetsuits by their doctor are exempt from the wetsuit rule and they are part of the competition.

Please email a doctor’s letter to leinsteropenseaswim@gmail.com or give it to the handicapper when registering before a race. If you are wearing a wetsuit you must tell the handicapper when registering at each race.

The wetsuit rule does not apply to the following races:

Irish Long Distance Swimming Association’s Great Dublin Swim

Q: One piece swimsuits

A: One piece swimsuits which cover the body, the arms, and the legs are allowed as long as they are made of a woven or textile materials. This is allowed to protect swimmers against anaphylactic shock as a result of jellyfish stings. Please show the swimsuit to the handicapper when registering if you are wearing a one piece swimsuit. The handicapper and the race team have the final say as to whether the suit qualifies as a swimsuit or as a wetsuit. The decision of the handicapper and the race team will be final. Please note special rules apply to one piece swim suits in the annual Jones Engineering Dublin City Liffey Swim.

For current news, check out our Facebook, Twitter or YouTube pages


The clubs listed on this page cater for masters swimmers and swimmers who compete in Leinster Open Sea swims.

City Centre
Irish Long Distance Swimming Association Markievicz Leisure Centre
Ben Dunne Gym (Crumlin)
North Dublin
3D Triathlon and Swimming Club Belvedere College Swimming Pool
Aer Lingus Masters Swimming Club National Aquatic Centre, Blanchardstown
Clontarf Waterpolo Club West Wood Gym Fairview, Clontarf
Eastern Bay Trinity Sports & Leisure Club Donaghmede
West Wood Gym Fairview, Clontarf
NAC Masters West Wood Gym Fairview, Clontarf
National Aquatic Centre Blanchardstown
North Dublin Waterpolo Swimming Club National Aquatic Centre Blanchardstown
Guinness Bicentenary Centre St James's Gate
West Wood Gym Fairview, Clontarf
St Vincents Water Polo Club National Aquatic Centre Blanchardstown
City Centre
Dublin Swimming Club Sportsco Ringsend
West Wood Gym Fairview, Clontarf
UCD Belfield (Dublin 4)
East Coast of Ireland Open Water Swimming 40 Foot Sandycove Dún Laoghaire
Garda Swimming & LIfesaving Club Guinness Bicentenary Centre, St James's Gate
LOS Masters dlr Leisure Loughlinstown Loughlinstown, Dún Laoghaire-Rathdown
Newpark Sports Centre Blackrock, Dún Laoghaire-Rathdown
dlr Leisure Meadowbrook, Ballinteer
Castle Park Sports Centre Dalkey, Dún Laoghaire-Rathdown
Guinness Water Polo Team Guinness Bicentenary Centre St James's Gate
Half Moon Swimming & Water Polo Club UCD Belfield
Mespil Mespil Swimming Pool, Ballsbridge (Dublin 4)
Phoenix Masters Swim Club Clondalkin Leisure Centre Clondalkin
Tallaght Masters Swim Club Tallaght Sports Complex Balrothery, Tallaght
Templeogue Masters Templeogue College Swimming Pool, Templeogue
Ben Dunne Gym Carlisle, Crumlin
Terenure SC Terenure College Swimming Pool, Terenure
Trojan Masters Swim Team Newpark Sports Centre Blackrock, Dún Laoghaire-Rathdown
Viking Swimming Club Ballyfermot Sports & Fitness Centre, Ballyfermot
Stewarts Sport Centre Palmerstown
Outside Dublin Area
Meath Masters Swimming Club Aura Trim Leisure Centre, Trim, Co. Meath
Lough Lene Collinstown, Co. Meath
Wexford Masters Swimming Club Wexford Swimming Pool, Ferrybank, Wexford
Whitford House Hotel Pool, Wexford Town
Wicklow Swimming Club Coral Leisure Centre, Wicklow Town

For current news, check out our Facebook, Twitter or YouTube pages


Leinster Open Sea committee

Brian Nolan


Noel Brown

Noel Brown

Committee Member

Willie Irwin

Willie Irwin

Committee Member

Lousie Morris

Louise Morris

Handicap Team

Colm O'Neill

Handicap Team

Brian McLoughlin

Committee Member

The committee are unpaid volunteers who work through out the year to ensure a successful and safe season of sea swims.

Special thanks to all our supporters

Jones Engineering

Dublin City Council

Dublin Port Company Limited

Swim Ireland

CJK Engineering


Fingal County Council

Dún Laoghaire Harbour Company

Dublin Fire Brigade

Dublin Civil Defence

An Garda Síochána


Green Tiger Group

Priority Construction

Sweeney Sheet Metal


The Sugar Club

Fitzgeralds Pub

Sports Surgery Clinic

Dublin Mini Coaches

Dublin Bay Cruises

Irish Crests

Feel Good Scuba

Clontarf Baths

Contact Us

Please contact us with any questions. Our email address is leinsteropensea2019@gmail.com. Include your phone number so that we can get back to you quicker.