Louis C. Clark Sanctuary

The Louis C. Clark Sanctuary is located on Valentine's Road in Old Brookville in Nassau County, New York on Long Island.

It was donated by Frances S. Weeks to The Nature Conservancy in 1965 in memory of her son, Louis C. Clark.

The swamp is characterized by cattail, buttonbush, red maple and tupelo; in addition, over 150 species of wildflowers and 25 species of shrubs and vines are found within the preserve.

There is also a range of animals that inhabit the swamp such as snapping turtles, green herons, and wood ducks.

A total of 0.75 miles (1.21 km) of trails are maintained on the property, which is open to the public.