Traveling to London and Brussels...which pubs?

My wife and I are traveling to London and Brussels tomorow and are wondering which pubs are a "must". We are staying with friends so they have local knowledge of the city so let us know of the hole in the wall tyoe places that we should definitely visit.

Go to the Cantillion brewery as well as Delirium Cafe when in Brussels.

The Harp in Covent Garden in London

Zinc_Saucier said:

Go to the Cantillion brewery as well as Delirium Cafe when in Brussels.

Click to expand...

An enthusiastic co-sign on both of these.

If you're looking for a good bottle shop as well, I enjoyed Beer Mania:
http://www.beermania.be/allnewbm.php
My wife and I got to talking with the owner, who was really friendly - turns out he's a brewer as well, and sells his beer in the shop (sort of a golden strong, if I remember right). Back then (~5 years ago?) it was just in a plain unmarked bottle, but it looks like they've stepped up the branding a bit. He also has a crazy-looking custom glass he serves it in.

Thanks guys! We already had Delirium on our list, and i will try to get to the other as well.