Roscrea stone castle was constructed in 1332. It comprises of a gate tower and two D-shaped corner towers, which were originally joined by a curtain wall. Access to the courtyard was by draw-bridge through the rectangular gate tower. Its chimneys and gables are early 17th Century features, but the lower levels of the Castle are the original stonework. The two towers housed three storeys, one of which has an octagonal interior called the "Duke of Ormond's Tower". Although the tower was much ruined conservation work has been carried out in recent years.

Damer House an example of pre-Palladian architecture. This elegant three-storey Georgian house with nine bay windows was built by Joseph Damer in the early 18th century in the courtyard of Roscrea Castle. One of the rooms is furnished in period style. It also has a restored mill displaying original St. Crónán's high cross and pillar stone. The house was used as a barracks in the 19th century and fell into poor condition, but it has been undergoing gradual restoration. Damer House forms part of a complex with Roscrea Castle and its related buildings and its grounds include an impressive garden with fountain. It also has a restored mill displaying original St. Crónán's high cross and pillar stone.

There is disabled access to the gardens only, guided tours are available on request and facilities include public car parking and toilets.