GRDC Major River Basins of the World (MRB) is an ongoing GIS project of the Global Runoff Data Centre (GRDC). It is provided for public use under the condition of full citation and reference to incorporated data from the HydroSHEDS database (Lehner 2013). This is the 2nd, revised edition 2020 and replaces the basin polygons and river lines of the edition 2007 (GRDC 2007).