In 1948, Guevara entered the University of Buenos Aires to study medicine. His "hunger to explore the world" led him to intersperse his collegiate pursuits with two long introspective journeys that would fundamentally change the way he viewed himself and the contemporary economic conditions in Latin America. The first expedition in 1950 was a 4,500 kilometer (2,800 mi) solo trip through the rural provinces of northern Argentina on a bicycle on which he installed a small engine. This was followed in 1951 by a nine-month, 8,000-kilometer (5,000 mi) continental motorcycle trek through most of South America. For the latter, he took a year off from his studies to embark with his friend Alberto Granado, with the final goal of spending a few weeks volunteering at the San Pablo leper colony in Peru, on the banks of the Amazon River.
