Wisłok is a river in south-eastern Poland, a tributary of the San River, with a length of 205 kilometres (18th longest) and the basin area of 3,528 km2. (all in Poland). The root of the name Vis-lok is Indo-European or pre-Indo-European.The first metal bridges on highways were built in Galicia. They were bridges on the Wisłok river in Rzeszów (1877) and Raba in Książnica (1877). The construction of the first latticework metal bridges in Poland's territories.