This walk will take you around the City, showing you the Guildhall, Mansion House, Bank of England, and Royal Exchange.
does the tour include the interior of the buildngs
That'a a good question. We've tried to email them to ask, but unfortunately their email address doesn't seem to work (http://www.cityoflondonguides.com/contact). It just keeps on bouncing back. We will keep on trying.
I doubt that it does, though. There are separate tours available for Mansion House and Guildhall (Craig has been on them both, and the Guildhall one is well worth doing). They are both working buildings, and you can't really do them in the short time available. They might go into the Royal Exchange though, because that's basically just a posh shopping centre.
But we will keep on trying to contact them and let you know.
where does this walk start?
From the City Information Centre. That's that weird angular building round the southside of St. Paul's, on the opposite side of the road, along St Paul's churchyard.