Portrun is a small amenity area on the western shores of Lough Ree, 8km south-east of the town of Roscommon town.
The village is centred on the cross-roads of the Bóthar Mor, the route of which is now used only by farm vehicles and walkers. It is served by a local road, which connects with the Athlone – Roscommon National Secondary Route (N61) approximately 4km to the west.
The local route comes to an end at Portrunny Bay. To the north the River Hind discharges into Lough Ree, east of Bracknagh.
Portrun is located in a low lying agricultural landscape which falls gently to the shores of Lough Ree.
The landscape is characterised by stone walls and mature hedgerows. There is a small cluster of houses and old graveyard within the old village.
Along the lands to the east there are good views of the lake and the newly enhanced marina which is a focus for boating and water-based activities and amenities as well as a new playground.