Hamilton Pool Preserve - Hamilton Pool is located off of hwy 71 in Travis county about a thirty minute drive from Austin,Texas. The is a natural pool created by an underground river that collasped and formed by erosion over thousand years. The erosion created this cave with stalactite growing from the celling, a waterfall flowing over the limestone along bolders along with moss along with emerald green swimming hole. The preserve includes about 232 acres of natural habitat and is home to the golden cheek warble. This place draws a lot of people want to enjoy this place on a hot summer days but if you want to come be sure and call ahead and make reservation. Over the years the place has been loved to death and you now need a reservation just to get in also it is also good to make sure it is open for swimming because it is a natural swimming hole no chemicals are added to the water so at times it get shut down due to high bateria counts. This nature preserver is part of the Balcones Canyonlands Preserve and is a protected environment.