I just had to talk about the incredible find in London - when they were remodeling the Notting Hill Underground station, they unearthed these unbelievably cool posters, which date from 1956-59. Apparently they were in an old elevator passageway, and are not accessible to the public, according to Mike Ashworth, Design and Heritage Manager for the London Underground.
I mean, wouldn't that be just the coolest thing? You're just going about your day, like every other, and you suddenly realize that you've discovered a gold mine. I would've felt like I was in a time warp! I mean, check out how great all of the posters still look! And they're all so colorful and have that fantastic mid-century clean-lined aesthetic. They're so happy and fun.
I've always loved these vintage posters - in fact, I've used some images of them in my artwork, which you can see here:
Many thanks to Grain Edit for posting this information originally and the links to the Flickr photos. Oh, and all of the photos (besides my artwork, of course) are credited to the London Underground.