Lough Key Forest Park sits on the shores of Lough Key near Boyle in County Roscommon, and it's one of those places that consistently surprises visitors who weren't expecting much. The park covers around 350 acres of mixed woodland — oak, beech, ash, and conifer — surrounding a beautiful lake scattered with 33 islands, several of which have their own ruins, legends, and stories.

The centrepiece of the lake is Castle Island, where the ruins of a 19th-century castle sit dramatically on a small wooded island just offshore. The castle was built by the King family, who owned the Rockingham estate that once occupied this land. The estate house itself was destroyed by fire in 1957, but the walled garden, ice house, tunnel system, and various estate buildings survive and can be explored within the park. The underground tunnel system — built to allow servants to move around the estate without being seen — is one of the more unusual features and can be accessed on guided tours.

For families, Lough Key is exceptional. The Boda Borg adventure experience offers a series of physical and mental challenge rooms. The adventure playground is one of the best in Ireland — a large, well-designed space with equipment for all ages. The Zipit Forest Adventure offers zip lines and aerial trails through the treetops. And the Lough Key Experience treetop walk gives elevated views across the lake and forest canopy that are genuinely spectacular.

The walking trails through the forest are well-marked and range from short, easy loops to longer routes around the lakeshore. The park is particularly beautiful in autumn when the mixed woodland turns gold and copper, and the lake reflections are at their most dramatic. Boat trips on Lough Key operate during the summer season and give a completely different perspective on the islands and the surrounding landscape.