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 Parramatta River is an intermediate tide-dominated, drowned valley estuary located in Sydney, New South Wales, Australia. With an average depth of 5.1 metres (17 ft), the Parramatta River is the main tributary of Sydney Harbour, a branch of Port Jackson. Secondary tributaries include the smaller Lane Cove and Duck rivers.