Border Security Zone of Russia
A Border Security Zone (Russian: пограничная зона) in Russia is the designation of a strip of land (usually, though not always, along a Russian external border) where economic activity and access are restricted in line with the Frontier Regime Regulations set by the Federal Security Service (FSB). For foreign tourists to visit the zone a permit issued by the local FSB department is required.
Source: Wikipedia — Border Security Zone of Russia (CC BY-SA 4.0)