El Potrero Chico is an internationally renowned rock climbing area in the Mexican state of Nuevo León, outside the town of Hidalgo, within Sierra del Fraile protected area. El Potrero Chico is a unique geological formation of limestone cliffs and spires, some as high as . Rock climbing There is a large range of different climbs, most of them in the 5.8 to 5.13 grade. The type of climbing can range from steep overhanging face to easy slab. The rock is usually quite sharp. The climbs are mostly situated in a canyon at the entrance of the park, while the interior offers undeveloped mountain terrain with many mountain biking routes, ranging from very easy to expert options. El Potrero draws rock-climbers from throughout Mexico and from around the world. It is considered one of the top 10 locations to sport climb in the world. In addition to well over 500 routes, the area boasts the second longest sport route in North America, Timewave Zero, with 23 pitches and over . New routes are continually being developed. Rock climbers from Austin, Texas, notably, Jeff Jackson, Kevin Gallahger, Craig Pacinda, and Alex Catlin, along with Colorado climber Kurt Smith started developing the area in the 1990s. Development continued in the 21st century, notably by first accentionists Alex Catlin, Ed Wright, and Dane Bass. Many climbers have attempted to build bridges with the local community, but there remains much work to be done. There are multiple guide books covering the area, some of which are linked under External Links below. Conservation The eventual status of the land is uncertain. Much of the area is a "protected zone" (not a Mexican national park), a legal classification of little actual consequence. After the Mexican Revolution of 1910, the land within the park was divided amongst the townspeople as per the ejido system. This means that the Hidalgo ejido commission currently owns and controls 99% of the climbing area. Weather The temperature can vary quite a lot from day to day and from sunny to shady areas. During the summer months however, it is recommended to climb in the shade only. Due to the shape of the canyon, the weather outside may be cloudy and raining, but sunny inside the potrero. It is always possible to find a shady area. In the winter months, the usually daily high is about 18 degrees C° (64 F°) yet