A unique natural area surrounds the pool, collapsed grotto and canyon. The natural area was formed by thousands of years of water erosion. Cultural remains date back over 8,000 years.

Prior to the 1800s, Tonkawa and Lipan Apaches lived in the area. In the mid 1860s, Morgan C. Hamilton owned the property now known as Hamilton Pool Preserve. In the 1880s, the Reimers, an immigrant family from Germany, bought the property to raise sheep and cattle.
However, the Reimers soon realized the value of the grotto as a recreational area and opened the property for public use. Around the turn of the century, only a handful of people had the transportation to come out and enjoy the cool, serene surroundings.

By the 1960s, and on into the 1980s, Hamilton Pool's popularity had soared, as visitors packed the legendary swimming hole. The land suffered from sheer numbers and few restrictions.

In addition to impact from the visiting public, cattle, sheep and goats grazed the delicate ecosystem for several decades, resulting in changes to the native vegetation. In 1980, the Texas Parks and Wildlife Department cited Hamilton Pool as the most significant natural area in rural Travis County. In 1985, Travis County purchased 232 acres from the Reimers family and implemented an aggressive land management plan to restore Hamilton Pool. Now, as Hamilton Pool Preserve, the lush fern-canopied cliffs are making a comeback, as are the rolling hills and meadows of the uplands.
Source Travis County Parks: https://parks.traviscountytx.gov/