Glenullin was one of the first areas in the county to organise Gaelic games and the local club, John Mitchel's GAC, based at Seán Ó Maoláin Park, has a number of football and camogie teams.

In the basin of the valley there is an ombrotrophic raised bog which, having suffered severe ecological damage by commercial peat extraction in 1994, is now a protected site.

The original football pitch in Glenullin was Tinkers Park in Coolcoscreghan townland, on the junction of the Lisnascreghog and Glen roads.

The site now consists of the ruined remains of a medieval church in the centre of a walled graveyard, a rock-souterrain and a ballaun stone.

Glenullin covers about half the total parish area, the remaining being in the village of Garvagh and the neighbouring hamlet of Ballerin.