Zasechnaya cherta

Zasechnaya cherta (Russian: Большая засечная черта, loosely translated as Great Abatis Line or Great Abatis Border) was a chain of fortification lines, created by Grand Duchy of Moscow and later the Tsardom of Russia to protect it from the raids of the Crimean Tatars who, rapidly moving along the Muravsky Trail, ravaged the southern provinces of the country during a series of the Russo-Crimean Wars. It also served as a border between the Muscovite State and the steppe nomads. As a fortification line stretching for hundreds kilometers, the Great Abatis Border is analogous to the Great Wall of China and the Roman Limes.

Abatis is a military term for a field fortification made by cutting down trees. The line was built from the felled trees that were arranged as a barricade. It was also fortified by ditches and earth mounds, palisades, watch towers and natural features like lakes and swamps. The width of the abatis mounts up to several hundred meters. In the most dangerous places the abatis was doubled, trebled etc., the gates and small wooden fortresses were created to check the passers. Peasants who lived nearby were forbidden to settle or cut wood in the area, but were obliged by authorities to spend part of their time supporting and renewing the fortifications. In the autumn, large areas of steppegrass beyond the line were burnt to deny raiders fodder.

Stone and wooden kremlins of the towns were also included in the Great Abatis Line. Among these towns were: Serpukhov, Kolomna, Zaraysk, Tula, Ryazan, Belyov. Other fortresses in the line were smaller ostrogs.

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