Hamilton Pool Preserve

Hamilton Pool Preserve is in the Texas Hill Country about 23 miles west of Austin, off Highway 71. The pool formed thousands of years ago when the dome of an underground river collapsed, leaving an open grotto. A waterfall about 50 feet high drops into jade-green water.

Large slabs of limestone sit along the water’s edge and stalactites hang from the ceiling above. Moss, maidenhair fern and cliff swallows live on the cliffs. The ashe juniper uplands around the grotto shelter the endangered golden-cheeked warbler, and the preserve also holds chatterbox orchids and eastern red bay.

The 232-acre preserve is part of the Balcones Canyonlands Preserve, a protected environment.

The Tonkawa and Lipan Apache lived in the area before the 19th century. In the 1880s a German immigrant family, the Reimers, bought the land to raise sheep and cattle. The Reimers soon saw the grotto’s value as a place for visitors and opened the property to the public.

By the 1960s it was a popular summer swimming spot, and the land suffered from the crowds and from decades of grazing. Travis County bought 232 acres in 1985 and began a land management plan that includes prescribed burns, prairie restoration, endangered species surveys and water quality monitoring.

In February 2021 a series of winter storms formed ice wedges in the overhanging cliff and rockfalls increased, which closed the pool. Part of it reopened for swimming in May 2022, but it has closed at times since then because of high bacteria levels, and the trail under the overhang remains closed.