Translations:Друга лінія оборони: дерев'яні стіни на скелях/1/en
The builders of the Tustan fortress made very good use of the natural terrain and supplemented the rocks with wooden structures. The second line of defence was a 2.90 m wide and 13 m high wooden wall which began at the foot of the Velyke Krylo.
At the junction, two vertical grooves were cut into the rock - they are still visible on the rocks as parallel lines. The cavity between the two wooden walls below was filled with small stones to make the structure massive and strong.