For some people it’s a daily rite. More moderate followers might go once a week, others again only on special occasions – perhaps on Christmas Day, after being forced by a more militant family member, or on Christmas Eve, to get it out of the way. No, I’m not talking about Mass. I’m talking about the Christmas swim.

The benefits are many. For starters, the sea is a source of healing. Swimmers – and some medics – claim that the sea relieves aches and ills of all kinds, from hangovers to sciatica, diabetes to depression.

On what can be a stressful day, with family at such close quarters, it can be a relief to get out of the house and rub shoulders with strangers in the fresh air and purifying waters. If you’re feeling sluggish after a big breakfast it revitalises the body, preparing you for the turkey dinner. The cold dip is also a good excuse for an early tipple – just to bring the body back to a sensible temperature. (Some people light bonfires on the beach to warm themselves and their fellow swimmers after the icy plunge.) And on a day that tends to focus on the material, a bracing swim might be the perfect antidote.

Most swims begin at noon; others begin at 11am, to follow morning Mass, and others again take tide into account. At most meetings there are more onlookers than swimmers, but if you think your heart can take it, then dive in. So, in no particular order . . .

1. Carlingford Lough, Co Louth

It’s more than just a quick plunge at the 10th annual Christmas Eve swim at Carlingford, where locals gather for the 150m swim from pier to pier. Safety boats monitor the short strait, and the Irish Red Cross is on hand to deal with more severe cases of the chills. Hot showers, soup and a cheering crowd await swimmers at Carlingford Sailing Club. Swimmers should gather in warm clothes at 11.45am for a noon start. Last year local swimmers welcomed a visiting crew from Camlough Lake, in Co Armagh, who swam the return leg in their skins as part of their training for the 2015 Ireland Ice Swimming Championships. Yes, you can take this a step further if you want to.

2. Annagh Lake, Co Cavan

Now in its 48th year, this annual swim sees members of the Cavan Icebreakers club take to the waters. With the softer sands of the seashore unavailable, swimmers wade into Annagh Lake on the count of three. The Nifty Fifty Santas parade towards the lake each year on a quartet of Honda 50s, ringing bells. The event’s organiser, Sean Walsh, hasn’t missed a swim since the inaugural Christmas dip, in 1968.

3. Skerries, Co Dublin

Skerries is not short of swimmers, so one Christmas swim for the north Co Dublin town just won’t cut it. There are now three swims on Christmas Day. The longest-standing of these, stretching back decades, begins when, at noon, the town’s residents gather in force at the slipway by Joe May’s pub. Or join the Frosties for their daily swim at “the Springers”, at the end of Red Island, where they’ve been daily dipping for 15 years. A more sedate affair kicks off at 11am on the South Beach, facing out to Colt, St Patrick’s and Rockabill Islands.

4. Forty Foot, Sandycove, Co Dublin

Santa suits abound for Ireland’s busiest Christmas swim. The queue for the rocky platform begins in the morning and doesn’t ease off until early afternoon. Buckets for half a dozen charities shake below the Martello tower where the opening scene of James Joyce’s Ulysses is set (and where there is now a museum named after the writer). You’ll find a smoother entry to the water just around the corner, in Sandycove itself, where bathers gather daily throughout winter.

5. New Pier, Wicklow Harbour

The “new” – or West – pier in Wicklow town, albeit 150 years old, is the perfect spot to watch Wicklow Swimming Club, plus friends and visitors, race towards the sea on St Stephen’s Day. Members of the 75-year-old club, who range from four to 84, will take socks in hand to collect for the local Meals on Wheels this year. You may know the pier already from a recent car advert that compares a child’s first jump off a pier to driving a BMW. Pull the other one.

6. Rosslare, Co Wexford

Rosslare Strand’s blue-flag beach hosts an enormous gathering at noon on Christmas Day. Last year the organiser lit a bonfire on a crisp but sunny morning, with Wexford living up to its “sunny southeast” title even in midwinter. Ample supplies of mulled wine and soup, as well as the bonfire, warmed the thousand-strong crowd who gathered at the shore, most of whom stood by to watch a mere 150 swimmers take to the sea.

7. Guillamene, Co Waterford

Guillamene is home to the east coast’s only remaining diving platform, but there are also a number of slipways into this natural deep-water bathing spot. A passionate swimming community has developed over the years, with a dedicated group of daily swimmers. It was once men only, as the sign, a relic of the past, attests. On Christmas Day the main crowd assembles between 10.30am and 11.30am; club members serve soup to the hundreds who gather.

8. Kilmurran Cove, Co Waterford

In 1983 a young man named Michael Power kickstarted a tradition of swimming at Kilmurran Cove on Christmas Day. He died suddenly the following year. The swim that took place on Christmas Day of 1984 was named in his honour. Over the past 30 years the Michael Power Memorial Swim has raised more than €600,000 for local charities. The foghorn sounds at noon, when hundreds race towards the sea.

9. Myrtleville, Co Cork

The Myrtleville Swimmers have been taking to the sea since 2010 – many members have completed marathon swims around the world – but dippers have been flocking to this picturesque cove south of Cork city each Christmas Day for generations. It was here that I first learned the trick of taking a gallon of warm water to throw over your head postswim – a Corkonian invention, undoubtedly. Be careful not to chat to local swimmers for too long or you’ll be signed up for a Channel swim before the new year. It’s the busiest day of the year at Myrtleville, so if you can’t find a parking space, travel 10 minutes down the coast to catch the bonfire-lit swim at Robert’s Cove.

10. Derrynane, Co Kerry

At what is arguably Ireland’s most beautiful beach, swimmers gather at noon on Christmas Day, a tradition that began here more than 20 years ago. The house in which Daniel O’Connell was raised overlooks the bay.

The area was much frequented by smugglers in the 18th century. Tea, brandy, butter, wool, salt and hides were bought and sold by Maurice “Hunting Cap” O’Connell, Daniel’s uncle. Maurice grew wealthy and afforded his nephew an education at King’s Inns. The nearby town of Caherdaniel is named in O’Connell’s honour.

11. Fenit, Co Kerry

You’ll have to be up early to make the 64th Christmas Day swim at Fenit. Traffic will line the road from Tralee as city dwellers travel to the coast for the biggest Christmas swim in Munster. More than 600 people will line the shore of Lockes Beach at noon, with the same number watching from the pier. Santa and Mrs Claus will lead a chorus of Jingle Bells before signalling the rush to the sea. The ritual is repeated twice for good measure.

12. Kilkee, Co Clare

Kilkee is a swimmer’s utopia. It’s blessed with the Pollock Holes, a natural reef pocked with deep pools that are replenished each time the tide recedes. Newfoundout, or Newfy to locals, has two diving boards where Richard Harris used to show off in his youth. He also swam a mile across the bay to the beautiful Byrnes Cove. At high tide in summer teens also gather at the town’s pier, but it’s the humble Kilkee Beach that hosts the annual Christmas Day swim at 12.30pm in aid of Kilkee Sub Aqua Club’s search-and-recovery activities.

13. Kerin’s Hole, Co Clare

This summer we were welcomed with open arms to swim in Kerin’s Hole cliffside pool, access to which had crumbled away – and been devastated by recent storms. It has been lovingly restored through fundraising and hard graft by the community of Miltown Malbay. Not 300m from Kerin’s Hole is White Strand Beach. The adults who swam in Kerin’s Hole as children now flock to the strand for their Christmas dip, albeit at the tardier time of 1pm.

14. Blackrock, Galway

In 1885 a rickety old board attached to a large A-frame stretched into the sea from Blackrock – the area’s first diving platform. It was replaced in the early 20th century by a more ambitious steel and wood structure that lasted into the 1940s before disintegrating. In 1954 another diving platform was designed by a local engineer, built by a local construction company, blessed by the local priest and opened – to men only. Bishops are said to have patrolled the area keeping male and female bathers apart. On Christmas Day the year-round Tribal Swimmers – male and female – are joined by seasonal dippers throughout the morning. The tide will be out in the west, so no diving this December 25th.

15. Inis Mór, Co Galway

The Aran island has a variety of swimming spots, the most famous of which is Pól na bPéist – home to the Red Bull divers in the summer, as well as to tourists who make the trek across the island in the hope that the tide is just right and the waters calm. Although the population of the island dwindles in winter, significant numbers meet for a post-Mass gathering on December 25th. Last Christmas Day saw swimmers diving off the RNLI boat as well as the pier, where waters are warmer than in the open sea.

16. Lough Lannagh, Castlebar, Co Mayo

What else would you be doing on Christmas Day other than working through 20cm of ice with a sledgehammer? The icy swims of 2009 and 2010 didn’t turn dippers away from their annual winter rite. A small crowed queued to take the plunge into a small icy hole. In more clement weather, swimmers are joined by swans, which are better dressed for the occasion. The lack of a Gulf Stream to warm these lake waters keeps the crowd small. “Hardy”, which is sometimes an overused word in swimming circles, is certainly not misplaced here.

17. Belmullet Tidal Pool, Co Mayo

“Back in the 1950s and 1960s it was men only who swam at Shore Road,” says Eva Reilly. That was until Reilly and friends defied the parish priest, despite being named at the altar, and made room for themselves at the shoreline. When the obscurely exotic tidal pool was built on Shore Road in the 1980s, Reilly took up the position of water safety officer. Locals traditionally enjoy their St Stephen’s Day dip at the nearby pier, but this year, after the passing of Reilly’s husband, the inaugural Noel Reilly St Stephen’s Day Dip will take place at noon to raise funds for Cancer Care West.

18. Rosses Point, Co Sligo

Earlier in the year I met the author Kevin Barry for a swim on the beach at Rosses Point. He reminded me of the wild nights that WB Yeats endured on the strand, taking tincture of cannabis, then available from chemists, to treat gum pain. Around the corner from the beach is Sligo Yacht Club, where things are almost as wild on Christmas Day as they were in Yeats’s time. Hundreds gather at noon to race towards the sea from the open pool known as Deadman’s Point.

19. Bundoran, Co Donegal

A couple of hundred metres to the right of Bundoran Beach a beautiful cliff walk brings you around to two unlikely sea stacks, between which is set a springboard. During the summer months locals and holidaymakers dive from both the springboard and the increasingly higher ledges of Rougey Rocks. The springboard is taken in during the winter for safekeeping, but crowds gather on the nearby beach and race toward the crashing waves of Bundoran Beach on Christmas Day.

20. Culdaff, Co Donegal

The Inishowen Peninsula feels like a county all of its own, set as it is on the northern tip of Co Donegal, bordered by Lough Swilly on one side and Lough Foyle on the other. The New Year’s Day swim at Culdaff Beach is the peninsula’s largest, with hundreds gathering on this beautiful, expansive strand at 2.30pm. Many swimmers cross the Border from Derry and farther afield to begin their new year with a refreshing dip in the north Atlantic.

Brendan Mac Evilly is the author of At Swim, a travelogue featuring 43 of the best places to swim in Ireland, to be reprinted in 2016