York, York, England, United Kingdom
The Multangular Tower. This tower formed the north west corner of the Region legionary fortress of Eboracum. It was built about 300 A.D. on the site of an older and simpler tower. The larger stonework at the top is medieval.
Listen to the audio guide for Multangular Tower stone plaque Free on WIP — starts by itself when you arrive, even with the screen off