visiting the big capital!

Ollie and I are planning to take a trip to London

for a few days at the end of this month.
Seen as we are both broke students it's also a trip on a budget.

We have a whole three days, and want to fit as much in as we can.

Aside from touristy things (which I have done to death)
I don't really know London very well.

So what I'm asking if for suggestions for some where nice to go.

Anyone able to help?

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