Adam is standing outside a public toilet next to the Monument in the City of London. Except it isn't a toilet any more... It's the Monument Micro Museum, a brand new museum all about the Great Fire of London, and it might just be the smallest museum in the world.

Will, who spent three years making it, shows Adam round. Inside there's a flame exhibition and a giant map where a tiny spark grows and spreads across the city, telling the story of the three days in 1666 when most of the City of London burnt down. City of London guide David Harry, better known as The London Spy, explains why this corner of London is so old, from Roman Londinium to the Emperor Claudius bringing elephants across the sea. And there's a surprise: a secret laboratory hidden under the Monument, built by Christopher Wren and Robert Hooke so they could look up at the stars!

PLUS: Bex and Dan follow the clues to Pudding Lane in a taste of our free Time Hunters walk around the City of London, and meet a baker who swears the fire wasn't his fault.

The Monument Micro Museum is free and open every day from 10am to 5.30pm. Find out more by searching for Monument Micro Museum.