Matterhorn Bobsleds is a roller coaster in Fantasyland at Disneyland. While it's not a "must do," it is also recommended. The minimum height to ride is 42 inches.
The first steel-track, multi-vehicle roller coaster, Matterhorn Bobsleds reopened in June 2012 after undergoing a massive refurbishment, with new single-seats and a taller, 42-inch height requirement.
Walt Disney World