Ashdown House was originally an 18th-century country house, completed by Sussex-born Benjamin Latrobe who was later one of the architects of the U.S. Capitol Building in Washington, D.C. and the front portico of the White House in Washington. Ashdown is a Grade II* listed building and is now a co-ed prep school. It is NOT OPEN to the public.
According to Coxe, the house is supposedly haunted by phantom footsteps on the stairs each 6th July.
For further information, please read Haunted Britain by Antony D. Hippisley Coxe.