Long Island is located in the
Hawkesbury River, near the township of Brooklyn and is close to Ku-ring-gai
Chase National Park, being managed by NSW Parks and Wildlife. Long Island Nature
Reserve is located further up river from Lion Island, and was dedicated in 1972,
along with Spectacle Island, as important for its natural and cultural values.
The reserve comprises over 73 hectares. A small area at the eastern end of the
island, which includes a railway tunnel and other buildings associated with
management of the railway is not part of the nature reserve, but managed by the
State Rail Authority.
Long Island is listed on the Register of the National
Estate for its scientific importance as a remnant of the natural environment of
Sydney, for the abundance of aboriginal sites it contains, and because of the
variation and distinctive characteristics of its vegetation.