Cool, I love when you can see things like that. Two other examples of little bits of History
1. On the Strand in Liverpool opposite the Balic Fleet Pub
there are some metal plates still attached to the wall - these are all that remains of the metal supports of the over head railway.
2. A bit further afield - on the way into Newcastle, on the A69 just before its junction with the A1 is part Hadrians wall and a bus-stop that appears to of been made out parts of said Roman Wall!