In grounds of 65 acres (26 ha) there is a Grade II listed neo-georgian mansion called Northcote House which was built in 1930 and in which notable features include the grand staircase and front portico. The ill-fated Sunningdale Agreement on power sharing in Northern Ireland was signed there on December 9, 1973.
The site housed the National School of Government and provided training, organisational development and consultancy courses for UK civil servants and private individual learners until its closure in March 2012. It then housed the privately managed Civil Service College. Within the grounds there are gardens and a lake, a restaurant, lecture theatres, training rooms, a swimming pool and 272 bedrooms in accommodation blocks that are named after distinguished civil servants.