Discover London’s castle – a secure fortress, royal palace and infamous prison Explore London’s iconic castle and World Heritage Site. Get up close to the Crown Jewels, meet the legendary Yeoman Warders and ravens and see the Tower like never before. The world's most famous jewel collection Discover the world-famous collection of treasures including more than 100 objects and over 23,000 gemstones. At the heart of the Crown Jewels collection are English Coronation Regalia – the sacred objects used in the coronation ceremony. See them at the Tower of London today.