The historic Lapstone Zig Zag Walk is an exciting bushwalking trail in Glenbrook that follows an old railway. This railway was built and used in the second half of the 19th century.
The walking track leads to the Top Points Lookout and the Knapsack Bridge, an imposing sandstone arch viaduct that was built to carry the Zig Zag Railway line across the Knapsack Gully.