World's Smallest Subway System

Over 1,800 meters with six stations, one of the world's smallest subway system is built in Mount Carmel, locating in the city of Haifa, the third largest city of Israel. Like an escalator, trains in the mountain bring passengers into the top of the mountain.

Source(s):

http://www.j-tokkyo.com/2012/02/09/44402.html