1951 Polish–Soviet territorial exchange
The 1951 Polish–Soviet territorial exchange or Polish-Soviet border adjustment treaty of 1951 was a border adjustment signed in Moscow between the People's Republic of Poland and the Soviet Union regarding roughly 480 km2 (185 sq mi) of land, along their mutual border. The exchange was made to the decisive economic benefit of the Soviet Union due to rich deposits of coal given up by Poland; these deposits were discovered well before World War II. Within eight years following the agreement, the Soviets built four large coal mines there with the total mining capacity of 15 million tons annually.
In exchange, the Soviet Union ceded part of the Ukrainian SSR's Drohobych Oblast (1939–1959): the city of Ustrzyki Dolne and the villages of Czarna (Ukrainian: Чорна Chorna), Shevchenko (whose name was restored back to prewar Polish name Lutowiska in 1957), Krościenko, Bandrów Narodowy, Bystre and Liskowate. All of this territory became part of the Krosno Voivodeship in 1975, and of the Subcarpathian Voivodeship on 1 January 1999. It was a stretch of barren land with low quality soil and without any natural resources.
Poland gave up part of the Lublin Voivodship, with the cities of Bełz (Ukrainian: Белз Belz), Uhnów (Угнів Uhniv), Krystynopol (Червоноград Chervonohrad) and Waręż (Варяж, Varyazh). All of this territory is now part of the Sokal Raion (Сокальський район), Ukraine.
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