Rathcroghan is a complex of archaeological sites near Tulsk in County Roscommon, Ireland. It is identified as the site of Cruachan, the traditional capital of the Connachta, the prehistoric and early historic rulers of the western territory. The Rathcroghan Complex is a unique archaeological landscape with many references found in early Irish medieval manuscripts.

Tulsk is a village in County Roscommon, Ireland, on the N5 national primary road between Strokestown and Bellanagare. It sits at around 19 km north of Roscommon town.