Despite the best efforts of defenders at Upnor Castle downstream the Dutch were able to successfully attack Chatham Dockyards in 1667, so major fortifications were built in 1755 at Fort Amherst. These initially consisted of a 9m wide ditch and a 3m parapet, with 34 canons providing substantial defence capability.
Fort Amherst also included many underground tunnels which were used to store and move munitions and defenders. The Fort is believed to be the most complete Napoleonic fortification in Britain, and was in use almost continuously for defence until the end of the second World War.
After hundreds of years service, the defences have now been made redundant by technological advances. But you can relive their importance on a guided tour, or just stroll though the grounds and contemplate how life would have been for the defenders of this important site in the 1700's
And for paranormal believers, there's the additional attraction of monthly ghost tours held in the tunnels at night.