Castletown House, Celbridge, County Kildare, Ireland, is a Palladian country house built in 1722 for William Conolly, the Speaker of the Irish House of Commons. It formed the centrepiece of an 800-acre (320 ha) estate. The estate was sold in 1965, and later sub-divided. The house and a core demesne of 120 acres were bought by a group of people looking to preserve them, and became the first major project of the Irish Georgian Society; they were later transferred to a dedicated charitable foundation, and ultimately to State ownership. Most of the wider estate remaining was divided between State forestry company, Coillte, and developers, and parts were built on, notably the former orchard and walled garden. In September 2023, the main access road and car parking became the subject of access issues and protests.

Celbridge is a town and townland on the River Liffey in County Kildare, Ireland. It is 23 km (14 mi) west of Dublin. Both a local centre and a commuter town within the Greater Dublin Area, it is located at the intersection of the R403 and R405 regional roads. As of the 2022 census, Celbridge was the third largest town in County Kildare by population, with 20,601 residents.