Montaña Infinitum, located in Mexico City's Chapultepec Park, was the first roller coaster in the world with three vertical loops. The structure is 111 ft (34 m) high and 3,444 ft (1,050 m) long; its maximum speed is 53 mph (85 km/h).
Animated digital simulation:
http://il.youtube.com/watch?v=JZQxOvAIS8k&feature=related