Hamilton Pool - True Beauty

37 km away from Austin (Texas, the USA) there is one of the most unusual and picturesque lakes in the world - Hamilton Pool. It's unsual because it is an undergroud and ground lake at the same time. The beauty is contributed by the waterfall falling from 15m height. The lake formed thousands of years ago due to the fall of a calciferous dome fold of the underground river caused by heavy erosion. The waters of the underground river fall into the river flowing nearby - the Pedernales river which, in its turn, is a tributary of the Colorado river.