Roscommon

The county town, with a Dominican priory holding the tomb of Felim O'Conor, king of Connacht, and a large thirteenth-century royal castle. 'Lady Betty', the county hangwoman of the 1780s, is one of its stranger memories.

Roscommon lay in the homeland of the Connachta, among kingdoms such as Uí Maine, Síol Muireadhaigh and Moylurg, and the surnames O'Conor, McDermott, Kelly, Beirne, Duffy, McDonough and Brennan come from this country. From 1118 to 1156 it was the seat of the diocese of Elphin. In 1945 a gold lunula and two gold discs, dated to between 2300 and 1800 BC, were found in the town.

Drawn from the History section of the Wikipedia article on Roscommon ↗, rewritten here and adding nothing it does not say; licensed CC BY-SA 4.0.

• Castlecoote · castle · 7 km
• Donamon Castle · castle · 9 km

Straight-line distances from the town centre, from each site's documented coordinates.

• Corlea Trackway · An 18-metre stretch of the great oak road of 148 BC, preserved in a climate-controlled hall exactly where the bog swallowed it.
• Rathcroghan (Cruachan) · Queen Medb's royal seat: 240 monuments over four square miles, including Oweynagat, the cave called 'the gate to Hell' — one claimed home of Halloween.
• Strokestown Park · The landlord here shipped 1,490 tenants to Canada in 1847, half died, and was shot dead that November. His house is now the National Famine Museum.
• Rathcroghan — Oweynagat · The 'cave of the cats', birthplace of Queen Medb and doorway to the Otherworld: at Samhain its creatures pour out into the world. One root of Halloween.
• Cruachan — Medb's court · Where Medb and Ailill's 'pillow talk' about whose wealth was greater started the Cattle Raid of Cooley — over one brown bull.

All of these are pinned on the Hidden Ireland map.