Lough Oughter

Lough Oughter is not really a lake with a shape. The last ice sheet left this part of Cavan covered in drumlins - low rounded hills of glacial debris - and when the water rose it filled every hollow between them, producing an intricate network of channels, bays and islands over a large area, with the boundary between land and water hard to define on any map. Boating through it is genuinely disorienting. On one of the islands stands Clough Oughter Castle, a circular thirteenth-century tower on a small artificial island, reachable only by water; it was where Owen Roe O'Neill died in 1649 and was one of the last strongholds to fall in that period. Killykeen Forest Park on the western side has trails, cabins and water access. The lake is a major coarse fishery. Navigation without local knowledge is confusing and the shore is largely reed and private land.

What you actually see

• The drumlin maze - water filling every hollow between rounded hills.
• Clough Oughter Castle - a circular thirteenth-century tower on an island.
• Killykeen Forest Park - the main access point, with trails and water frontage.
• The fishery - one of the better coarse fishing systems in the country.

When to go

April to October for the water and the trails. Fishing runs year-round. Winter flooding raises levels and makes shore access poor.

Honest expectations

The castle can only be reached by boat and there is no landing service - most people see it from the water or across it. Navigation is confusing without local knowledge. Shore access is limited by reeds and private land.

Nearby

Cavan Burren Park is west; Killykeen and Killeshandra are on the lake.