North of Fiambalá on Ruta Provincial 34, the landscape changes abruptly. The road passes through Medanitos on asphalt, then turns onto a dirt track that leads across 30 kilometres of open terrain to the dune complex at Tatón. What appears from the approach to be simply a large dune field resolves, on arrival, into something considerably more imposing: the Duna Federico Kirbus, named for the Argentine adventurer and journalist who measured and documented it, rises 1,234 metres from base to crest to reach a summit elevation of 2,845 metres above sea level — by the most commonly cited measure, the highest sand dune in the world.
There is no entrance fee and no guide required — you drive the TR4 directly onto the dunes. The face itself is at roughly 45 degrees, steep enough to require commitment, and the reward at the top is the view: the dune drops away sharply on the far side into a dry valley, the Andes rise as a continuous wall to the west with peaks above 6,000 metres visible in multiple directions, and the silence at this altitude on a windless afternoon is absolute. Sandboards can be rented in Fiambalá town before heading out — driving up and boarding down is the obvious combination.
Fiambalá is a small town at 1,550 metres in the Departamento Tinogasta, sitting at the foot of the cordillera where Ruta Nacional 60 begins its climb west toward the Paso San Francisco and the Chilean border. The Pianwalla — "penetration into the high mountain" in the language of the Cacano people who inhabited this valley before the Spanish — is the name the original inhabitants gave to this place, and it remains apt: Fiambalá is the last town before serious altitude. The Termas de Fiambalá, 15 kilometres north on the road to Tatón, are the morning's plan. Tonight is camp.
Deleting this waypoint is permanent and cannot be undone.