The aerial tram with some of the most dramatic and unusual views on this list was not built for the purpose of sightseeing. The Medellin Metrocable was built to supplement the city's public transportation system. Locals use the service to travel up the steep slopes of valley in which Medellin sits. By most estimates, 30,000 people ride the three lines of the cable car network every day. Built in 2004, the system was intended for use by residents of the poorer hillside neighborhoods who did not have access to bus routes because of the extreme steepness of the local roads. But the cable cars are also attractive to sightseers, who are able to see panoramas of almost the entire city as well as the lush valley landscapes that characterize this part of northern South America.