Amsterdam Nieuw-West is a borough (stadsdeel) comprising the most western neighborhoods of the city of Amsterdam, Netherlands. The borough was created in 2010 after a merger of the former boroughs Osdorp, Geuzenveld-Slotermeer and Slotervaart. In 2013, the borough had almost 142,000 inhabitants. Most of the residential neighborhoods of Amsterdam Nieuw-West were built after 1950 under an urban expansion plan, based on the garden city concept. Centrally located within the borough is Sloterplas lake and the Sloterpark.