Juan Eusebio Oiarzabal Urteaga (born 30 March 1956), commonly known as Juanito Oiarzabal, is a noted Spanish Basque mountaineer and has written four books on the subject. He was the sixth man to reach all 14 eight-thousander summits, and the third one in reaching them without supplementary oxygen. He was the first person to conquer the top 3 summits twice (Everest + K2 + Kangchenjunga), and was the oldest climber to summit Kangchenjunga, at almost 53, until Carlos Soria Fontan made his successful attempt in 2014, when he was 75 years old.