One of the places we visited while in London was the Tower of London. It was really impressive and was the location of so much history. While visiting, I highly recommend taking a tour (even though I rarely recommend taking a guided tour of anything) as you will get to hear so many more stories and interesting facts than you would walking it yourself.
This particular stairwell led to a room where many prisoners were held and carvings could be seen on the walls. Such prisoners as William Wallace, Anne Boleyn, Thomas Moore, and Thomas Cromwell spent their last days within these walls and left their mark there.
It is a fascinating place to go!