Using real locations in your writing

Image from the amazing SilentUK.com

Despite the fact that Sanctuary is set in the future I still used a lot of locations from modern-day London.

I could tell you exactly where each mission in the story took place. I could tell you the route the characters took through London, where they encountered scary things and where they found up friends.

I've been to London a good few times so it's not all that difficult to picture it. Using a named city really brings a reader closer to the action because they know the locations. The Sanctuary is based around Westminster and I've gone into a lot of detail with regards to the surrounding Tube system.

Further away from the base I began to use Google Streetview to picture potential places for campsites, small settlements and more scary things. The research then got even more exciting when I was looking at the state of some abandoned Tube stations.

So, I just wanted to know, do you use named cities in your work? Or do you prefer the freedom of an unnamed location?