Madrid's Metro – Old station of Chamberi (line 1), now part of the Metro museum.

The platform, separated from the tracks with a glass wall. This station is between two stations of Line 1, so trains pass pretty quickly and pretty often. There's no access to the other platform, but it's been cleaned and restored, showing old adds and projected images of both Madrid and its Metro in the old days.

Photo by Alberto Rueda (ad.rueda@gmail.com)