The Art O'Neill Challenge
A 55km night hike/run out of Dublin into the Wicklow mountains to Glenmalure
February and March
Mountain biking heats and races for all ages and levels. Begins in Ballinastoe, Co Wicklow, followed by more races in Ballyhoura, Limerick, Derroura, Galway and Ticknock, Dublin.
A 24-hour, 250km unsupported endurance race of kayaking, cycling and running across north-west Donegal.
Gaelforce Mountain Run
A 22km unmarked run through the northern Maamturk mountains in Connemara. A shorter 12km option is available.
An off-road mucky event involving slipping and sliding across 10km of cross-country obstacle course. Delirious, filthy fun.
Walk the Line
A 28km hike from Stepaside to the Hell Fire Club and back. In aid of Dublin Wicklow Mountain Rescue Team.
St Patrick's Quest, Killarney
A one-day 55km run, hike, cycle and kayak through Killarney National Park and the eerie, forbidding expanse of Black Valley. (A shorter 33km route is possible.)
Bray 10km Cliff Run
A 10km run from Greystones to Bray in Co Wicklow along beaches and cliffs.
Quest Glendalough Wicklow
A 57km run, cycle and kayak through the Wicklow Mountains and national park. (Shorter 41km and 19km routes available)
TEAR 24-hour Adventure Race
April 30th-May 1st
Twenty-four hours of kayaking, mountain biking, trekking/hill running, orienteering and rope-work for two-person teams in Lacken, Co Wicklow, with a two-hour sleep window allowed. Challenging and fun.
Connemara Adventure Challenge
32.5km of trail running, cycling and kayaking (or a 29km duathlon without the kayaks).
Enduro World Series Round 3
A series of downhill mountain bike challenges in Carrick Mountain, Co Wicklow, as part of the 2016 Enduro World Series. The best bike riders in the world compete, with Biking.ie later facilitating the public to try it .
Women With Altitude 2016
Women With Altitude arranges hikes, courses and trail practice for women under a Mountaineering Ireland initiative to encourage women to take on greater challenges in mountaineering. Its May climb is in association with Gartan Outdoor Education Centre, Co Donegal.
26 Extreme Coast to Coast Multisport Race
Non-stop, two-day race – cycling, running, kayaking 316km – from Enniscrone in Sligo to Newcastle, Co Down.
Ring of Beara Cycle Kenmare
A 140km cycle along a coastal route on the glorious Beara Peninsula through Castletownbere, Glengarriff and Kenmare.
Mourne Way Marathon
A marathon (with shorter alternative routes) along the trails of the Mourne Way.
A 64km run/hike, cycle and kayak challenge through Glenveagh National Park and up Mount Errigal in Donegal. There's also a shorter 44km option, or a duathlon which skips the kayaking.
Kilkee Hell of the West Triathlon
An Olympic Distance Triathlon begins with a 1,500m swim in Kilkee bay, then 44km cycling, followed by 10km run out along the Loop Head coastline.
Moxie Adventure Race
60km of kayaking, biking and running around the Blessington Lakes, with shorter 27km and 40km options.
The Gleneagle Run Killarney Marathon
A classic marathon along the Ring of Kerry and Killarney National Park. A half-marathon joins the race at Moll's Gap, with a shorter mini 10km run beginning from Gleneagle Hotel.
Women's Adventure Race Galway and Adventure Duathlon
27km of cycling, running/walking and kayaking for women around Killary Fjord. There's a duathlon version which avoids the water.
Dublin City Liffey Swim
2.2km race through the centre of Dublin from the Guinness Brewery, past Temple Bar and O'Connell Bridge to the Custom House. To qualify for a place in the race you need to compete in some previous races.
Lough Dan Swim
75 swimmers get a chance to race either 5km or 10km in the mountain lake in Wicklow.
Bike, kayak and run around Achill Island on various courses ranging from 18km to a 63km route which includes 1.2km swim or 2.5km kayak, 15km run and 45km cycle.
Women's Adventure Race Wicklow
24.5km cycle, kayak and running race for women from Roundwood, Co Wicklow. There's a duathlon option that avoids the kayak.
Blacksod Point Challenge triathlon
A gruelling Olympic-distance triathlon. Starts with a 1,500m Atlantic swim, followed by 41km cycle through north-west Mayo and ends with a 10km run across the sand dunes of Fál Mór.
Causeway Coast Marathon
A coastal marathon around Northern Ireland's glorious Causeway Coast. Multiple route options from mini to ultra. There's also a walking option in aid of Northern Ireland Chest ,Heart and Stroke Association
Running/hiking, biking and kayaking around Killarney National Park and the Gap of Dunloe in various distances from 27km to 70km.
The Great Fjord Swim
A 2km swims in the fjord between Mayo and Connemara, with shorter options facilitated by bringing participants some of the way across by boat.
The Wall - Adventure Duathlon
An immersion in the Mourne Mountains with a 3km run in the Silent Valley, followed by a 45km cycle and 15km of running to cover 63km in total.