[Josh Grisdale]

It has been ages since I have been, so, I suggest you read this article by Cory Lee – one of the most famous accessible travel writers.

Here are his thoughts on accessibility in London:
https://www.handiscover.com/content/tips-articles/wheelchair-accessible-london/

But the Visit London website mentioned above also has very thorough information on accessibility including accessible tours, attractions, hotels, public transit for wheelchair users etc:
https://www.visitlondon.com/traveller-information/essential-information/accessible-london

I wonder if the escape rooms mentioned by @NinaMorel are wheelchair accessible?

As a kid, I think the Tower of London was my favourite 🙂