Cuatro Caminos

Cuatro Caminos is a station on Line 1, Line 2 and Line 6 of the Madrid Metro, located underneath the Cuatro Caminos roundabout on the border of Chamberí and Tetuán districts in Madrid. It is located in fare Zone A. The station was inaugurated on 17 October 1919, and was opened to the public on 31 October 1919.The station is the deepest in the Madrid Metro system, with its Line 6 platforms located 45 m below street level. However, in terms of absolute elevation above sea level, it is not the lowest, as there are other Line 6 stations with platforms at a lower elevation.

Source: Wikipedia