Travnik Fortress or Old Town Travnik is located in the central Bosnian town of Travnik.
Some archaeologists and historians believe that there was a Neolithic settlement here. The old town was built in the first half of the 15th century during the reign of the Bosnian king Ostoja or King Tvrtko II. Kotromanić. It is not known how the Turks conquered it, but it is known that they upgraded and expanded the fortress. During the Austro-Hungarian period, the fortress was called Kastel or Kaštel.