Babak Fort

Pāpak Fort  or Babak Castle is a large citadel and National Symbol of Iranians on the top of a mountain in the Arasbaran forests. It has been identified as the stronghold of Pāpak Khorramdin, the leader of the Khurramites in Azarbaijan. The castle, built on 2300-2600 meter heights, surrounded by gorges as deep as 400 to 600 meters, is believed to belong to the Parthian dynasty and modified under the Sasanid dynasty.

You will need hiking boots, a sun hat, plenty of water, and at least 3 hours for the climb, and 2 hours for the descent.