To be honest, in my ignorance I pictured the Tower of London as...well...a tower.
It's not. This cool picture was taken by my daughter after we got off the subway in the dark. My contribution was tripping over a curb I didn't even see and falling on the ground. Luckily, there were no witnesses. (Thank goodness it was dark.)
But many an unfortunate soul was brought by boat to Traiter's Gate...
The outer walls of the Tower of London were topped by walk ways.