London Bridge has a secret entrance nestled on the north-side of the river in St. Magnus the Martyr Church and a fascinating history, subject to plagues, wars and fires. @southwarknews London Bridge has a secret entrance hidden behind centuries of history and there’s even a 2000-year-old Roman surprise!? ?St. Magnus the Martyr Church, Lower Thames … Continue reading London Bridge has a secret entrance hidden behind centuries of history and a 2000-year-old Roman surprise