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.

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.

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.

The ride today bears little resemblance to actual spaceflight. But in the 50 years Space Mountain has been running, there have been and still are several nods to NASA.

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

• Jan. 15, 1975: Space Mountain opened at a cost of $15 million, the Sentinel reported, “an amount more than the whole cost of Disneyland, built in 1955.” Astronauts Scott Carpenter, James Irwin and Gordon Cooper posed with Mickey Mouse, who is decked out in a spacesuit.

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.