The Yuri A. Gagarin State Scientific Research-and-Testing Cosmonaut Training Center is a Russian training facility responsible for training cosmonauts for their space missions. It is located in Star City, Russia—a name which may refer to the facility itself and to the grounds on which it is located. Star City is an area in Moscow Oblast, Russia. The facility was originally known only as Military Unit 26266 , and was a secret training base for Soviet Cosmonaut candidates. The site was chosen for its proximity to Moscow and other infrastructure that would be essential for its function

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