Hueco Tanks, Archaeological site and rock formation in El Paso County, Texas.

Hueco Tanks is an archaeological site and rock formation in El Paso County, Texas, made up of three syenite mountains, a weak form of granite. Stacked boulders and slabs of reddish-brown rock rise in a broad mound, their cracks and hollows holding rainwater for months. A pale gravel path curves toward the outcrop through low green brush.

The Jornada Mogollon population established settlements with pithouses starting around 1150 and farmed the land near the water sources. Later, Apache groups used the rocks as camps and shelter before Spanish and American settlers reached the region.

The natural water basins in the rocks led travelers to stop here for centuries and leave messages on the walls. These layers of rock paintings, spanning different eras, show masks, figures and symbols from several cultures.

Access to most areas is only possible with guided tours that must be booked in advance through the park administration. The trails are often uneven and require sturdy footwear and enough water in warm weather.

The depressions in the rocks create tiny habitats with higher moisture where plants and animals thrive that otherwise only occur in wetter areas. Some of these water basins persist even in dry months and form small oases in the middle of the desert.