A friend and I were going to go to Greenwich today and explore for a bit, but the friend now has less time. We still want to go out and see something different, but will probably have to stay in zone 1.
If the majority of people in London have heard of it, we’ve probably done/seen it or don’t want to.
So what else is there to do/see in central London in 2 hours or less that’s fun but not generally known about?