Dover Castle, Kent

Since the 12th century, the impressive Dover Castle also referred to as the "Key to England", has been perched atop the well-known Dover white cliffs. But the castle itself is only a small part of Dover Castle. Dover Castle, with its hidden tunnels from World War II, Roman lighthouse, and St. Mary in Castro church, is one of the best castles to see in England.

For more than 900 years, Dover Castle has stood guard over the shortest sea route connecting England to continental Europe. With a property size of about 30 acres and the largest and most expensive keeper in the nation, it also claims to be England's largest castle. At Dover, there is more than enough to keep you busy all day. There are more than 80 acres of gardens to explore, historic sites and furniture, exhibits about the building's involvement in World War II, and those spectacular views across the English Channels toward France.