Situated on the banks of the River Medway, this attractive turreted castle is set in a picturesque village area backed by rolling, wooded hills.
Upnor Castle was originally built on the orders of Queen Elizabeth I in 1559 as a gun fort to defend her warships at anchor in the reaches of the Medway and Chatham Dockyard.
Although the castle was an important link in the defence line, it was not well maintained and proved ineffective when the Dutch, under the command of Admiral de Ruyter, sailed up the Medway in June 1667 to attack the dockyard. The enemy fleet met very little resistance and when it left two days later, it had destroyed or captured a large number of the Royal Navy ships anchored at Chatham.
https://www.visitmedway.org/attractions/upnor-castle-2819/