The private spacecraft company founded by Elon Musk has struck a deal with Space Adventures to begin offering tourist flights on its first Crew Dragon flight.

Up to four people will have the chance to break the world altitude record for private citizen spaceflight. The flight is expected to take place sometime around late 2021.

The partnership fulfills Musk’s desire to use the Dragon spacecraft as a means to ferry people to and from space. It also presents competition for Richard Branson’s Virgin Galactic, which is being built with space tourism in mind.

“This historic mission will forge a path to making spaceflight possible for all people who dream of it,” said Gwynne Shotwell, president and chief operating officer at SpaceX in a statement.

Space Adventures has a long history in space tourism, hosting eight missions to the International Space Station since 2001. The Crew Dragon flight will take people to twice the altitude of the ISS, roughly as high as the Gemini space craft flew.

The Crew Dragon made its first unmanned flight to the ISS last March. NASA contracted SpaceX to ferry astronauts to and from the ISS in the spacecraft after the Space Shuttle was retired.

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