Villavicencio Nature Reserve, 365 Curves Road & Uspallata Valley Day-Trip Guide

Before the modern lakeside highway through Potrerillos opened along the Río Mendoza gorge, travellers crossing the Andes from Mendoza to Chile followed the older northern mountain trail along Ruta Provincial 52 through the Precordillera to the Uspallata Valley. Today, this 62,000-hectare corridor forms the Reserva Natural Villavicencio (a designated Ramsar wetland and wildlife reserve), offering a spectacular loop day trip that pairs a famous 1940 alpine hotel with wild herds of guanacos, condors, and San Martín's 1817 campaign heritage.

1. Reserva Natural Villavicencio & the Iconic 1940 Tudor-Normandy Hotel (1,750m)

• The Historic Hotel Termas de Villavicencio & Terraced Gardens: Driving fifty kilometres north-west of downtown Mendoza across the semi-arid Monte plains, Ruta Provincial 52 enters a green mountain ravine at 1,750 metres where mineral-rich springs emerge from the Precordillera. Here stands the postcard-famous Hotel Termas de Villavicencio (inaugurated in 1940 and featured on every bottle of Villavicencio mineral water across Argentina). Although the guestrooms closed in 1978, the beautifully restored white-and-timber Tudor-Normandy facade, the stone chapel, the visitor interpretation centre, the forest adventure park, and the sweeping terraced gardens of pines and roses are open daily for walks and lunch at the Parador Villavicencio; check the official reserve portal for seasonal opening hours.

2. The Road of 365 Curves (Caracoles de Villavicencio), Paramillos & Uspallata

• Climbing the 365 Switchbacks Among Wild Guanacos & Condors: Immediately above the hotel gate begins the Camino de las 365 Curvas (Los Caracoles de Villavicencio), a dramatic nineteen-kilometre gravel mountain road engineered in the early twentieth century that winds up the sheer canyon wall to 3,000 metres. Because hunting is strictly banned inside the reserve, herds of wild guanacos (Lama guanicoe) graze right beside the road, while Andean foxes, choiques (lesser rheas), and Andean condors soar across the abyss.
• Cruz de Paramillos (3,000m), Jesuit Silver Mines & Uspallata Valley (1,900m): Cresting the pass at the Balcón de los Caracoles and Cruz de Paramillos (3,000m) reveals a sweeping full-frontal panorama of the glaciated wall of Cerro Aconcagua and the ruins of the seventeenth-century Jesuit silver and lead mines of Minas de Paramillos (note that driving over the unpaved upper pass to Uspallata requires a high-clearance vehicle and clear weather). Descending into the green oasis of Uspallata (1,900m), visit the beehive-shaped adobe smelting domes of the Bóvedas de Uspallata (used by Friar Luis Beltrán in 1816 to cast cannonballs for the Army of the Andes) and the pre-Inca petroglyphs of Cerro Tunduqueral before returning to Mendoza along paved Ruta Nacional 7 via Potrerillos.