Roki Tunnel
Crossing the Caucasus Mountain range was an important section of the northern arm of the Silk Route. There was one pass on the southeast end in Derbent (known as the Caspian Gates or Gates of Alexander), and multiple passes throughout the range: Jvari Pass at 2379 m and above the Darial Gorge on the Georgian Military Road, Mamison Pass on the Ossetian Military Road at 2911 m, and Roki Tunnel at 2310 m.