Fifty years ago this week, Space Mountain opened in Magic Kingdom at Walt Disney World. The original Space Mountain, which opened at Walt Disney World in 1975, was the first fully-enclosed, dark roller coaster and the first to be controlled by a computer.

Walt Disney wanted to build Space Mountain at Disneyland a decade before the indoor roller coaster forever altered the skyline of the Magic Kingdom a few years after the debut of the Florida theme park. Disney’s Magic Kingdom theme park will celebrate the 50th anniversary of Space Mountain on Wednesday, Jan. 15.

For fifty years now, guests to Magic Kingdom have had the chance to travel amongst the stars when riding Space Mountain. The iconic Tomorrowland coaster opened on January 15, 1975

Space Mountain in Walt Disney World celebrates 50 years of operation. Initially opening on January 15, 1975, Space Mountain, an indoor steel rollercoaster themed to space travel, has been a staple of Tomorrowland, the area of the Magic Kingdom park where the ride resides.

A cultural touchstone, the dark ride opened to the public on Jan. 15, 1975, three years and three months after the Magic Kingdom’s debut.

Space Mountain is one of the most recognizable theme park attractions around the world, but here’s what you may not know about the beloved ride.