Frustratingly, there are no public buses south from Barreal or the national park along the RN-149 – still mostly unpaved on this stretch – to Uspallata in Mendoza Province. The scenic RP-400 strikes out in a southwesterly direction from Barreal to <strong>Las Hornillas</strong>, over 50km away. This tiny hamlet is inhabited mostly by herdsmen and their families amid pastureland and gorse scrub and is effectively the base camp for the mighty <strong>Mercedario</strong>, which looms nearby. If you want to climb this difficult but not impossible mountain, regarded by many as the most noble of all Argentina’s Andean peaks, contact Fortuna Viajes in Barreal. The nearby rivers are excellent for fishing for trout; ask at the tourist office in Barreal.