Baikonur Cosmodrome Site 31

Baikonur Site 31, also known as Site 31/6 at the Baikonur Cosmodrome, in Kazakhstan, is a launch site used by derivatives of the R-7 Semyorka missile. Since Roscosmos' change from flying crew on the Soyuz-FG to the Soyuz-2 launch vehicle for crewed flights in 2020, it has served as the primary launch site for Soyuz flights to the International Space Station. It took over from Site 1/5 (Gagarin's Start) after the latter failed to receive funding to modernize it for the slightly larger Soyuz-2 rocket.

Before that, it only saw a handful of crewed flights when Site 1/5 was unavailable (Soyuz TMA-06M, Soyuz TMA-15M, Soyuz MS-02).

It was first used on 14 January 1961, for an R-7A ICBM test mission. As of 2023 it is currently used for Soyuz-2 launches. In the 1970s and early 1980s, several crewed missions were launched from the site.