Svaneti, like other parts of the northern Caucasus, was at times a section of the Silk Road from China as it worked its way from Asia to the Black Sea and the ancient trading port of Phasis (today’s Poti). In the 6th century, as Persia and Byzantium fought for control of these important trade routes, the Byzantine Emperor Justinian pushed the routes up through the high mountains in order to avoid his Persian foes. Elaborate defensive walls were constructed to shelter and defend the caravans from local mountain tribes. Mestia was one point along the route that passed through Ushguli before moving down to Lower Svaneti and Kutaisi. Some time later, Christian missionaries established monasteries in Svaneti and settlements grew around the churches. After 1453, and the fall of Constantinople, the Silk Road across the North Caucasus ceased to be used.