The University of Sussex, established in 1961 as the first of the plate-glass universities, is a campus research intensive university between Stanmer Park and Falmer, four miles (6 km) from the city centre. The university is home to the Institute of Development Studies and the Science Policy Research Unit, amongst over 40 other established research centres, and has been ranked first in the world for Development studies by the World University Rankings. Served by trains (to Falmer railway station) and 24-hour buses, it has a student population of around 20,000 students of which about a quarter are postgraduates. The university has been ranked 40th in the UK by the Complete University Guide in its 2021 rankings and 246th in the world by the World University Rankings of 2021.