Kottbusser Tor is a Berlin U-Bahn station located on lines U1, U3, and U8. Many Berliners use the affectionate term Kotti.
It is located in central Kreuzberg. The area has a bad reputation for the relatively high, mainly drug-related crime rate, instances of which have recently become quite rare in most other parts of the district. The original Kottbusser Tor was a southern city gate of Berlin; the road through the gate led via the Neukölln suburb to the town of Cottbus.
Trivia - K and missing h rely to a language reform at begin of 20th century. See e.g. Stralauer Tor, or Cölln and Neukölln.
Wikipedia https://en.wikipedia.org/wiki/Kottbusser_Tor_(Berlin_U-Bahn)
Address 1 Kottbusser Straße, Berlin 10999, Germany
Coordinates 52°29'56.347" N 13°25'5.918" E