Yellow Fortress, Hattusa

Hattusha Upper City fortifications on a natural rock outcroppingwith access possible only from the southeast side, where still exist remains of the bastion, walls and gate.

Sources:

1. Philipp Niewöhner, The Archaeology of Byzantine Anatolia: From the End of Late Antiquity Until the Coming of the Turks, Oxford University Press, 2017, pp. 61 f