Columbia University Tunnels
students are exposed to endless worlds of myth and lore, to historical facts and mathematical findings. But if they want to explore the school's own legends, they'll have to do so on their own. Columbia's extensive tunnel system connects most of the buildings on the Morningside Heights campus and has a deep history: while some underground paths date back to when Columbia was an insane asylum, others housed the beginnings of the Manhattan Project. Students also took advantage of the tunnels during the 1968 student strikes. Although most of the tunnels are currently closed to the public, that hasn't stopped students from taking it upon themselves to master their twists and turns and leave cryptic (and not so cryptic) tags on their weathered walls.