Waterfalls of the Charco del Hervidero Nature · San Agustín del Guadalix, Cuenca del Medio Jarama, Madrid The river Guadalix drops here over two waterfalls set in a gorge of willows, alders and poplars. It is reached in about five kilometres from the Laguna de los Patos recreation area, along wooden walkways that cross the riverbed several times. Photo: U-95 (CC BY-SA 4.0) What to see and do in San Agustín del Guadalix