Cow Tower, Norwich 
“One of the earliest purpose-built artillery blockhouses in England, this brick tower was built in c.1398-9 to command a strategic point in Norwich’s city defence.…” – official site
Ease by public transport:
Unknown
“One of the earliest purpose-built artillery blockhouses in England, this brick tower was built in c.1398-9 to command a strategic point in Norwich’s city defence.…” – official site
Ease by public transport:
Unknown