If you were asked to picture London during the Middle Ages, you might think of The White Tower, Westminster Abbey or Guildhall - some of the capital’s most famous landmarks. But scratch beneath the surface and you’ll find there are lots more clues to this medieval metropolis.

In the second episode of 'Hidden London', London tour guide Katie Wignall seeks out the London of the Middle Ages - a city of narrow streets and soaring spires, almost completely destroyed by the Great Fire of 1666… and the Blitz during the Second World War. But despite the devastation and centuries of development, not all of that city is lost.

Katie start her tour at the London Charterhouse, which has been home to many significant moments in London's history since 1371. It has been a monastery, grand mansion, boys school and an almshouse, which it remains to this day. More recently, Charterhouse square was dug up as part of London's cross rail construction and a mass burial dating back to the Black Death in the 14th Century was discovered.

Next, Katie visits part of the Roman Wall which used to surround the old city. She then touches upon the history of London Bridge which has undergone reconstruction twice in the few centuries and looks very different from the heavily built upon medieval bridge - home to some of the wealthiest citizens at the time.

After passing several significant medieval palaces, rivers, churches, stones and clinks, Katie arrives at her final destination - St John's Priory. Headquarters of the Knights Hospitaller, the monks who lived there in the Middle Ages took vows of poverty, chastity, and obedience, and were expected to fight on crusade in the Holy Land if called upon.