Roscommon Castle is a dramatic and imposing 13th Century Norman Castl. It was built in 1269 by Robert de Ufford, Justiciciar of Ireland, on lands he had seized from the Augustinian Priory. It was besieged by the Connacht King Aodh O'Connor in 1272 and eight years later it was again in the hands of the English garrison, and fully restored. By 1340 the O'Connors regained possession of it, and held it for two centuries until 1569, when it fell into the hands of Sir Henry Sidney, Lord Deputy. In 1641 the Parliamentarian faction gained it until Confederate Catholics under Preston captured it in 1645. It remained in Irish hands until 1652 when it was partially blown up by Cromwellian "Ironsides" who had all the fortifications dismantled. It was finally burned down in 1690 and gradually fell into decay.
Today, the Castle's past can be explored while enjoying adjacent Loughnaneane Park and Playground , a 14 acre recreational area. The natural features of the park include a turlough and a wildlife conservation area which is a habitat of unique flora and fauna. A deck is provided for visitors to view the wildlife and views beyond. There is also a swallow-hole on the site. The Park includes a crannog known locally as the Hill o' Bones, a wildflower meadow, bird walk, lake feature, mounds, children's playground and car park.