King's Lynn, Norfolk, England, United Kingdom
St Ann's Fort. This open square and the brick arched wall to the north are the last traces of the gun battery known as Saint Ann's Fort. Built in 1570 it was repaired and re-gunned against various seaborne threats to the town, 1625-1815.
Listen to the audio guide for St Ann's Fort green plaque Free on WIP — starts by itself when you arrive, even with the screen off