London Photowalks - need suggestions!

So, as part of my Things To Do In 2013, I want to do a photowalk around something/somewhere in/near London.

I need suggestions for where to go, and possibly thematic ideas.

This could be something like iconic pubs, a museum (that allows photography, obviously), a location, a theme (possibly developed over several walks, like Famous SF Locations or something), or ... anything really.

Things to keep in mind:

• I am a wuss when it comes to weather. My camera is not rainproof, and it rains a lot here. Also, it's cold out there this time of year.
• My back hurts a lot, camera gear is not light. At least in the early part of the year, keeping things to locations where I can sit down and put my bags down a lot is a great idea.

... that's about it, really.

So, non-Londoners, is there something you'd like to see photographs of?  Londoners, what's interesting to see around here?

There will be prizes for the 12 I pick - namely, I will print out and send you a photo of your choice from the nominated photowalk. In case of duplicate successful suggestions across different social media, I will duplicate prizes up to the limit of my laziness.

See my smugmug galleries for what I've already taken pictures of.