photo by Joe Lomas, via his Flickr photostream

Go ahead and take a guess of where this nice black-and-white candid image was taken. Answer is after the jump.

To submit a photo or photos of something transportation-related, post them to Metro’s Flickr group or email them to sourcemetro@gmail.com. The photos we’ve featured can be seen in these galleries on Flickr. Or click on the ‘art of transit’ below.

That’s Metro Line 6 in Madrid, Spain.