In 1959, Maestri, together with Cesarino Fava and Austrian guide Toni Egger [it], travelled to Patagonia to attempt the north-east ridge of the unclimbed Cerro Torre.

Among the doubters are many well-known alpinists including Carlo Mauri, who had failed to climb the mountain in 1958 and in 1970, Reinhold Messner,[3] and Ermanno Salvaterra,[4] who had defended Maestri until successfully completing roughly the same route himself in 2005.

Besides citing the impossibility of the climb given the ice-climbing tools available in those years, the critics point out that Maestri's description of his route is detailed and accurate up to a glacier substantially lower than where Cesarino Fava claimed to have turned back, but vague and impossible to trace on the mountain thereafter; and that bolts, pitons, fixed ropes and other equipment used by the 1959 expedition is plentiful up to that glacier, but absent thereafter.

[7] In 2015, Rolando Garibotti and Kelly Cordes showed the photo Maestri claimed was taken on the summit of Cerro Torre, was taken on Perfil de Indio.

Over two seasons, he used a petrol-driven air compressor, weighing approximately 135 kg (300 pounds) to drill 400 bolts into the rock, and lay thousands of metres of fixed ropes.

[13] On 21 January 2012, Austrian climbers David Lama and Peter Ortner made the first free ascent of the southeast ridge, proving the face was climbable without the use of bolts.