Unexpected day in London!

[GemGEmGemster]

Have come to London for a work thing that’s now been cancelled - meaning I have a whole day to myself tomorrow!! What should I do? I don’t know London at all but don’t want to do the typical touristy things.

I would love to go to one of the big cemeterys starting with highgate

Portobello Road market, Kensington Gardens and pop into the Serpentine galleries if you can book a slot.