Old townhouse style building set in front of juxtaposing high risers makes for an odd placement, but internally it's a quirky spectacle. One half is dedicated to the sale of antiques - anything from old door handles to hallways lined with hunting trophies. The other half is a relaxed bar and hidden gourmet dining area constructed of similar furnishings [all for sale too]. Even if you don't wish to spend £'s, a walk around the place is advised.
This may not be much of a secret but deserves a mention. I find it hard to go anywhere near this place without having to go there. Freshly baked Beigels hot salt beef and it never closes, 24 hours a day 7 days a week.
Founded in 1828 the museum houses around 67,000 specimens many of which are now extinct or endangered. My favorite is the skull of a Bottlenose Whale from 1860.