Lane Cove River

The Lane Cove River, a northern tributary of the Parramatta River, is a tide-dominated, drowned valley estuary west of Sydney Harbour, located in Sydney, New South Wales, Australia. The river winds through a bushland valley and joins Parramatta River at Greenwich and Woolwich, where together they form an arm of Sydney Harbour, and serves as a border along with Middle Harbour separating Sydney's North Shore.

The Lane Cove River rises near Thornleigh and flows generally south for about 15 kilometres (9.3 mi). Its catchment area is approximately 95.4 square kilometres (36.8 sq mi).

The upper reaches are in a narrow, forested valley eroded into the North Shore Plateau. Fiddens Wharf was the site of early 19th century logging. The middle reaches are impounded by a weir just upstream of Fullers Bridge. Sections of the valley are forested and are protected within the Lane Cove National Park, an area of 598 hectares (1,480 acres), formerly a State Recreation Area. The lower reaches of the Lane Cove River, downstream from the weir near Fullers Bridge, are tidal and merge into Sydney Harbour at Greenwich and Woolwich. There are significant areas of mangrove communities along the shores.

The confluence of the river with Scout Creek is in Lane Cove National Park at Cheltenham. At North Epping, still within the confines of the national park, it is joined by Devlins Creek from the south and Terrys Creek near Macquarie Park. South–west of Killara and Lindfield, the width of the river expands, continuing south through Lane Cove River National Park, towards the suburbs of Linley Point and Riverview, before finally reaching its mouth between Greenwich Point and Woolwich, where it merges with Parramatta River and soon after becomes part of Port Jackson, more commonly known as Sydney Harbour.

Devlin Creek was named after the Devlin family, who lived in Willandra, a historical house in Ryde.

The area surrounding the river, no more than 1 kilometre (0.62 mi) wide, is called Lane Cove National Park, and is a site of ecological importance, listed on the Australian Register of the National Estate. It contains an endangered community of fungi, some species of which have still not been classified.

A popular caravan park and campground known as Lane Cove River Tourist Park is located on the western side of the valley above the river.

The Lane Cove River is the site of many old trails and tracks, some of which have survived from logging days. They are now used for recreational purposes. Some of them have been incorporated into the Great North Walk, a long-distance walking trail from Sydney to Newcastle. This trail passes along the Lane Cove River between Boronia Avenue, Hunters Hill, and Thornleigh Oval, Thornleigh. On the east side of Thornleigh Oval, the trail makes use of Lorna Pass, a track built during the Depression of the 1930s to provide relief work. The pass was named after Lorna Brand, who raised money for the work. Another trail, the Lane Cove Valley Walk, stretches from Thornleigh to Lindfield.