Mount Edgcumbe in Cornwall was built nearly 100 years before the Mayflower set sail in 1620. The Tudor style mansion stands at the top of an equally ancient double avenue of trees. The Mount Edgcumbe family can trace back their Devon ancestry over 500 years. The House was built between 1547 and 1553. For the first time in England a house was built to take advantage of the situation and views rather than as a defensive house built around a courtyard.
Cothele, Cornwall - my favourite National Trust property along with Lanhydrock House and St. Michael's Mount.