Guards at the Tower of London..

[@KnightsbridgeStudios]

Yes, what they were doing is changing the guard for the next 2 hours. Anyone who does get in their way after the warning will get marched over, and anyone foolish enough to stand in front of them after the warning deserves to get run over.

[@Mistah33YT]

This is the tower of London, not tower bridge. Tower bridge is next door :P