Frogmore House is a 17th-century English country house owned by the Crown Estate. It is a historic Grade I listed building. The house is located on the Frogmore estate, which is situated within the grounds of the Home Park in Windsor, Berkshire. Half a mile south of Windsor Castle, Frogmore was let to a number of tenants until the late 18th century, when it wa…Frogmore House is a 17th-century English country house owned by the Crown Estate. It is a historic Grade I listed building. The house is located on the Frogmore estate, which is situated within the grounds of the Home Park in Windsor, Berkshire. Half a mile south of Windsor Castle, Frogmore was let to a number of tenants until the late 18th century, when it was used intermittently as a residence for several members of the British royal family.