Story highlights Tim Peake, 3 crew members landed Saturday in a Soyuz capsule

"What an incredible journey it has been," Peake says

(CNN) Britain's first astronaut aboard the International Space Station is back on Earth after a six-month mission.

Tim Peake landed in a Soyuz capsule in Kazakhstan on Saturday morning. He was accompanied by Russian cosmonaut Yuri Malenchenko and U.S. astronaut Timothy Kopra, who've spent 186 days in space with him.

"What an incredible journey it has been-- thank you for following!" Peake tweeted before the Soyuz spacecraft took off.

Touchdown! #Soyuz brings home @Astro_Tim, @Astro_TimPeake and Yuri Malenchenko after 186 days in space at 5:15am ET/9:15am UTC. — Intl. Space Station (@Space_Station) June 18, 2016

Peake, 44, made the most of his time in space.

He ran the London Marathon strapped to a treadmill, held a science lesson for 300,000 schoolkids and ventured out of the space station on his first spacewalk.

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