There’s a really fun tour to do for the Tower Bridge. The Tower Bridge is the bridge across the Thames right next to the Tower of London. The Tower of London was built in the 11th century but the Tower Bridge was built in the later 19th century. It could raise & drop based on steam-powered (coal-powered) pistons that would do all the work. You can do the tour over the bridge (not for the acrophobic of us but we did it anyway!!) & underneath it to see the machines that did all the work. It is all a part of what makes London great!