Originally Posted by
flatlander
The Tower isn't small; it will take a couple of hours to go around the armouries and the Crown Jewels if you want to go there.
Could be combined with a visit of Tower bridge. The glass floor and the machine room can be quite interesting.
Originally Posted by
flatlander
Then take the Tube Circle line from Paddington (which is air conditioned these days, unlike the deep Tube lines, and has larger train carriages too) to Tower Hill.
Wouldn't it be quicker to take the Bakerloo to Embankment and from there there the circle line. The circle line makes quite a detour either way between Paddington and Tower Hill. BTW I don't think you have to worry much about the lack of A/C around this time of year.