Early history of the surrounding area of Ufa dates back to Paleolithic times. Presumably, from the 5th to 16th centuries there was a medieval city on the site of Ufa. On the Pizzigano brothers' map (1367) and on the Catalan Atlas (1375) a town approximately on the Belaya River was designated Pascherti (Bashkort), and Gerardus Mercator's map (1554) also marked the settlement with the name Pascherti. French orientalist Henri Cordier associates the position of Pascherti with the current location of Ufa. Ibn Khaldun called the town, among the largest cities of the Golden Horde, Bashkort. Russian historian of the 18th century Peter Rychkov wrote that there was a great city on the territory of Ufa before the arrival of the Russians. The official of the Orenburg Governorate government Vasily Rebelensky wrote that Ufa was founded by the Bashkirs. By order of Ivan the Terrible a fortress was built on the site of modern Ufa in 1574, and originally bore the name of the hill it stood on, Tura-Tau. 1574 is now considered to be the official date of Ufa's foundation. Town status was granted to it in 1586. Before becoming the seat of a separate Ufa Governorate in 1781, the city, along with the rest of the Bashkir lands, was under the jurisdiction of the Orenburg governors. And even though the 1796 reform reunited Orenburg and Ufa again, in 1802, the city of Ufa became a new center of the entire Orenburg Governorate that included large territories of modern-day Republic of Bashkortostan, Orenburg Oblast, and Chelyabinsk Oblast. Monuments were erected in two of the city's graveyards to commemorate those shot and buried in the 1930s, during and before the Great Terror. The Belaya River Waterway (1870) and the Samara-Zlatoust Railroad (1890) connected the city to the European part of the Russian Empire and stimulated the development of the city's light industry. During World War II, following eastward Soviet retreat in 1941, the Abwehr operated in Ufa, 1941–1943, some German infiltration, occurred 1914–1943 in espionage, many industrial enterprises of the western parts of the Soviet Union were evacuated to Ufa. On 4 June 1989, the Ufa train disaster occurred about 75 kilometers away from the city when a pipeline leak released gas near a railway line. When two trains approached, the sparks from the brakes of one train ignited the gas, causing an explosion which killed 575 people.