Nevado de Toluca holds a distinction unique in Mexico: it is the only volcanic crater in the country that can be reached by automobile. That accessibility has been both the park's greatest draw and one of its most serious problems. Until July 2008, cars, motorcycles, and ATVs drove directly onto the soft sandy soil of the crater floor, causing damage that experts have described as critical. Vehicles are now banned from the crater area, and visitors must walk between two and six kilometers from the parking area, choosing between a longer, flatter route and the steeper Paso del Quetzal. Cattle are also forbidden. How long these restrictions will remain in place is unclear, but the damage they were designed to address is visible -- tire tracks carved into terrain that took millennia to form. The crater and its twin lakes remain the park's main attraction, drawing up to 10,000 visitors on a single day.

When the national park was established in 1936, it protected roughly 54,000 hectares of forest and volcanic landscape 45 kilometers from Toluca and 135 from Mexico City. Today it covers only 17,000 hectares. Much of the lost land was forest, and its removal has diminished the region's ability to replenish aquifers -- each year, two springs disappear as water tables drop. In the remaining parkland, more than half the original tree biomass has been lost to a combination of agriculture, illegal logging, and mineral extraction by rural communities that depend on the income. The forests that survive -- firs at lower elevations, pines at middle altitudes, broadleaf trees in the piedmont -- are weakened and vulnerable to pests and disease. In 2010, proposals were made to redesignate the park as a biosphere reserve, which would provide stronger legal protections. The park spans parts of twelve municipalities, principally Toluca, Zinacantepec, and Calimaya.

The two shallow lakes inside the crater are more than a scenic destination. Archaeological investigations have recovered numerous pre-Hispanic offerings from the water -- copal incense and ritual objects deposited during ceremonies whose details are largely lost but whose physical evidence survives in the cold, high-altitude waters. These are among several archaeological sites within the park. The volcano has been extinct for so long that its crater has become a landscape in its own right, with its own fragile ecology. The National Institute of Anthropology and History has documented millennial-old objects recovered from the summit, linking Nevado de Toluca to the broader pattern of high-altitude ritual sites across Mesoamerica where mountains were considered sacred thresholds between the human and divine worlds.

Nevado de Toluca is Mexico's fourth-tallest peak, and its proximity to two major metropolitan areas defines everything about the park's challenges. Most visitors come from Mexico City and the State of Mexico. The Toluca metropolitan area continues to expand toward the park's boundaries. In the 1990s and early 2000s, proposals for a 19-lane ski resort on the volcano's north side generated controversy before local residents pushed back, concerned about losing access to their lands. The park offers hiking, mountain biking, and horseback riding, along with limited skiing when conditions allow. But recreation is secondary to the park's role as a water source: the forested slopes of the Nevado feed the aquifers that supply surrounding communities. As those forests shrink and the population grows, the tension between conservation and livelihoods only sharpens. The volcano's indigenous names -- House of the God of Waters, White Mountain -- turn out to describe not just what the place looks like but what it does.