The Nepean River is a river in the coastal region of New South Wales, Australia.
The headwaters of the Nepean River rise near Robertson, about 100 kilometres south of Sydney and about 15 kilometres from the coast. The river flows north in an unpopulated water catchment area into Nepean Dam, which supplies water for Sydney. North of the dam, the river forms the western edge of the Sydney Basin, flowing past the towns of Camden and Penrith, south of which flowing through the Nepean Gorge. Near Penrith it is joined by the Warragamba River. North of Penrith, at the junction of the Grose River near Yarramundi, the Nepean becomes the Hawkesbury River.
The luscious banks of the Nepean River provide a natural haven for local flora and fauna and a quiet location for local residents to relax. At Emu Plains, the western bank of the river provides a location for outdoor theatre productions on warm summer nights. The eastern bank at Penrith provides barbecue facilities and children's play equipment, as well as a wide pathway running for several kilometres for strolls along the riverbank. The eastern bank is also the home of the Nepean Rowing Club.
Bass bite at dusk during and just after the bats have finished their drinking.