The Museum of London site (now closed as they prepare to move to their new site, coincidentally near the AWS HQ), and there was a window you could look down on part of the wall, which you can also see from the other side of the road near Barbican. I won't give directions, as that seems futile anywhere near Barbican, but I had only just thought about how weird it is that there is wall at Tower Hill, and wall at Barbican - they can't be the same run of wall as it was built, can they? That'd be immense...
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