Wow! I hadn't known much of anything about the Wallace Collection before a friend of mine asked me to join her in checking out this museum in Marylebone, but now I am itching to go back for more! The Wallace Collection sits in a grand mansion on Manchester Square not far off of Oxford Street, and has a very extensive collection that has an impressively wide range. From paintings to sculptures and from an amazing collection of intricate (and largely still functioning!) ornamental clocks to fine French porcelain, this place is pretty amazing. Plus, it's got free entry!
Make sure that you give yourself enough time if you want to be methodical about it and see everything, because there is a lot more than you might realize. After spending well over an hour on the ground floor, taking in the collections of marble busts, antique furniture, old medallions and coins and an armory that brought out the knights and squires obsessed middle schooler in me, I couldn't summon the energy to do the upstairs galleries justice and will have to return again, as the first floor consists of a lot of paintings as well as collections of jewelry and yet more delicate porcelain vessels.
I guess that the Wallace Collection isn't as unknown to the world as it was to me, but it is still a rather off the beaten path museum to take in instead of the jam-packed National Gallery or British Museum, and I'll definitely steer visiting friends towards this place when they come to London.