Although it's believed that the secretive Freemasons were originally formed in the medieval era, still very little is known about them. We know it's a mens-only group, comprising powerful, wealthy individuals including some famous ones - Sir Winston Churchill and several members of the royal family were part of it. But just how much power do they wield, and what do they use it for? Is the secrecy because they're actually really sinister? The answers to some of these questions can be found at the Museum of Freemasonry, which explains the ranking system of the organisation and the meaning of the symbols they use. It's on the site of their England headquarters at Freemasons Hall. This building is worth a snoop just to take in the spell-binding architecture, with its stained glass windows and mosaic patterns depicting masonic symbols.