Argentina🇦🇷 | national parksSan Guillermo National ParkVicuña herds, puna plateau, guided 4x4 tracks | things to do and best time to go

Here's what most sites won't tell you: San Guillermo isn't really a hiking park in the Patagonian sense, it's a high-altitude vicuña sanctuary where the 'trails' are mostly dirt tracks meant for 4x4 vehicles, not boots. It sits in San Juan province, up near the Chilean border, spread across a desolate puna plateau above 3,000 meters. You get guanaco and vicuña herds everywhere, zero crowds and no entrance fee. On the downside, there is almost no infrastructure, the altitude is extreme, and you can only enter with a local guide and a 4x4. Compared to nearby Ischigualasto, it's rawer and far less visited. I remember gasping for air at 4,200 meters, watching a vicuña herd freeze mid-stride, breath clouding in the thin, cold air.

There's no lodging inside San Guillermo itself, just a ranger post with basic facilities. Backpackers base themselves in Rodeo, a small town about five hours away by winding dirt road with budget cabañas and simple hostels, or in San José de Jáchal, which has more services and transport connections. Camping is possible near park boundaries with prior arrangement through park authorities. Neither town is touristy, so expect modest, no-frills accommodation rather than backpacker hubs with social scenes.