Overview
Castle Lake is a 50-acre lake ringed by Coillte forest just south of Bailieborough in County Cavan, with two easy waymarked loops, some quiet fishing stands and the low ruins of a planter’s castle in the trees. It’s free, level for the most part, and if you only have an hour the short lake loop is all you need – the longer one is for when you want the history. The Irish name for Bailieborough, Coill an Chollaigh, means ‘forest of the boar’; there are no boar now, but the old woodland feel survives, strongest in spring under the oaks.
The two loops
Both walks start at the lakeside car park on the north-west shore, on a firm gravel forestry track that stays close to the water. The shorter Lake Loop runs about 3.5 km (blue markers) and takes roughly an hour. The longer Castle Loop adds a second circuit for about 6.5 km in total (purple markers, allow two hours) and takes in more of the historic sites. It’s gentle going, with a modest climb at most, and fine for families and for dogs on leads. The route is signed as part of the national looped-walk network, under the name PJ’s Way.
History in the trees
The clearest relic is the low stone footprint of Bailieborough Castle. It was built by William Bailie, a Scottish planter granted the land in the early 1600s, who had the demesne enclosed by 1629. Much later, from 1915, the Marist Brothers occupied the house; it burned in 1918 and was finally demolished in the 1930s. Their headstones remain in a small woodland graveyard along the longer loop. Nearby, a memorial marks those who died at Rebel Hill in the 1798 rising, one of several older features, alongside a rath on the hill itself.
Wildlife and the seasons
The lake and its wetland edges hold mute swans, mallard, cormorants and grey herons, with a chance of grebes out on the water. Watch the stone bridge where the river leaves the lake for dippers and, if you’re lucky, a kingfisher. Spring is the standout, when bluebells spread under the oak and beech; autumn turns the canopy gold, and in a hard winter the lake can freeze to a flat calm. The short loop stays walkable year-round.
Practical information
- Access and parking: free parking in the tarmac car park on the north-west shore, which is the trailhead for both loops. Reach it on the R191 from Bailieborough.
- Fishing: a well-stocked coarse fishery with bream, roach, perch, pike and eel. Bream fish best from April to October; roach and pike are there year-round. Access and parking are good, with stands along the shore.
- Facilities: none on site. There are picnic benches by the car park, but no toilets and nowhere for refreshments, so bring what you need.
- Etiquette: paths are firm but can be wet near the stone bridge after rain. Keep to the marked trails, keep dogs under control, and take your litter home.
Nearby
- Bailieborough Castle – the plantation-era site and demesne tied directly to this walk.
- Annagh Lake – a larger open-water lake north of the town, for swimming and angling.
- Cavan Burren Park – a drive west, with dolmens, wedge tombs and waymarked trails.
- Castle Saunderson – a historic house and gardens giving a fuller picture of Cavan’s landed estates.
For the fishing, April to October is the window for bream; for everyone else, catch it in May when the bluebells are out.