The Hamilton Pool Preserve is a historic swimming hole with 50 foot limestone waterfalls. During droughts the waterfalls slow to a trickle. Swim at your own risk (when swimming is allowed). There are no lifeguards on duty. Swimming is sometimes prohibited due to high bacteria levels. For updated swimming conditions please call (512) 264-2740 before you come.
It is just under a mile upstream from its confluence with the Pedernales River. The pool trail is 1/4 mile in length and includes a series of rock steps descending into the canyon. The trail is rugged and steep. Sturdy footgear is recommended. Visitors with physical disabilities can arrange assistance into the canyon by requesting a ride by preserve staff. The ride takes a visitor into the canyon, but not all the way to the pool, since no vehicle can make it to the pool.
Hamilton Pool Preserve is a natural pool that was created when the dome of an underground river collapsed due to massive erosion thousands of years ago. The pool is located about 23 miles (37 km) west of Austin, Texas off Highway 71. Since the 1960s, Hamilton Pool has been a popular summer swimming spot for Austin visitors and residents. Hamilton Pool Preserve consists of 232 acres (0.94 km2) of protected natural habitat featuring a jade green pool into which a 50-foot (15 m) waterfall flows with water temperatures reaching 50 degrees Fahrenheit.
The pool is surrounded by large slabs of limestone that rest by the water's edge; large stalactites grow from the ceiling high above. The ceiling and surrounding cliffs of the grotto are home to moss, maidenhair fern and cliff swallows. The Ashe juniper (cedar) uplands of the preserve are home to the endangered golden-cheeked warbler.
The natural pool and creek are not chemically treated, so water quality is monitored regularly and swimming is occasionally restricted. Hamilton Pool is part of the Balcones Canyonlands Preserve and is a protected environment.Provided By: https://en.wikipedia.org/wiki/Hamilton_Pool_Preserve