Matienzo Base (, or more often Base Matienzo or Estación Matienzo) is an Argentine Antarctic base and scientific research station named after Lieutenant Benjamín Matienzo, an Argentine aviation pioneer. It is located in Larsen Nunatak, one of the Foca Nunataks, in Graham Land, Antarctic Peninsula. Matienzo is one of 13 research bases in Antarctica operated by Argentina. From 1961 to 1985 it served as a permanent base; since then it is open during the summer season only. History Matienzo was founded as Lieutenant Matienzo Joint Base () on 15 March 1961 as a joint effort between the Argentine Army and the Argentine Air Force. Under the command of then Captain Ignacio Carro, several aircraft and tracked vehicles were employed to transport more than of cargo from Esperanza. At the end of 1962 Matienzo was the launch site for the first major Air Force operation in the Antarctic. In what was called Operación Sur ("Operation South"), a Douglas C-47 (TA-33) commanded by then Captain Mario Luis Olezza took off from the base trying to reach the South Pole and then land on McMurdo Station. This first attempt failed due to a fire in the airplane's engines. The plan could only materialize in 1965. On 15 November 1963 the base was transferred under exclusive command of the Air Force, and renamed as Destacamento Aeronáutico Teniente Matienzo ("Lieutenant Matienzo Aeronautical Detachment"), The Air Force kept a number of planes for exclusive service of the base. During 1964 an extensive program of meteorological and climatological observations was fulfilled: it included studying the glaciological profile across the Matienzo–Esperanza route and the coastal channel route between the Robertson Island and the 72° 30' S position. Also, topographic and aerial photographic surveys of the Larsen Ice Shelf were made. In 1965 two Gamma Centauro sounding rockets developed by the Argentine Air Force and two high altitude balloons carrying instruments for x-ray measurements where launched from the base, under collaboration with the University of Tucumán and the Instituto de Investigaciones Aeronáuticas y Espaciales. That year the base name was changed to the present one. On 29 July 1968 a Beaver P-05 took off from Matienzo with the mission of assisting a critically ill medical patient in the British Base "F" on the Argentine Islands. Amidst very bad weather, the aircraft crashed without casualties and the evacuation had to be delayed until the icebreaker ARA General San Martín could