The Jasper Ridge Biological Preserve is a 1,200 acre (5 km²) nature preserve and biological field station owned by Stanford University, located at 37°24′29″N 122°13′39″W / 37.408°N 122.2275°W south of Sand Hill Road and west of Interstate 280 in Portola Valley, California. It is used by students, researchers, and docents to conduct biology research, and teach the community about the importance of that research. The preserve encompasses Jasper Ridge and Searsville Lake (actually a reservoir) and the upper reaches of San Francisquito Creek, along with the latter's Corte Madera Creek and Bear Creek tributaries.