How Many Times Have You Walked Into A Hole In The Ground?

we call it the Tube,

 others call it the Underground, Metro or Subway, but I am guessing none of the holes in the ground are as intriguing or popular as this one, the Bockenheimer Warte subway entrance in Frankfurt, Germany, photograph via Reddit,

the station, erected in 1986, was built to look as if an old tram car had crash landed into the sidewalk that surrounds the station, the entrance was designed by the architect Zbigniew Peter Pininski who was inspired by René Magritte, a surrealist painter, think of his self portrait, Son of Man, above photograph @MojoBeast, what a great way to enter the Tube, talk about thinking out of the box.