From the website
S7 Airlines
The airline has the widest domestic route network in Russia, created on the basis of two air transport hubs at Moscow (Domodedovo) and Novosibirsk (Tolmachevo). It also has regular flights to the countries of the CIS, Europe, the Near East, South-East Asia and to countries in the Asia-Pacific region.
The airline’s story began in 1957, with the first civil flight from a military airport in Novosibirsk, by the Tolmachevo united air group; Sibir Airlines was based on that group. Since 2005 Sibir Airlines has operated under the brand S7 Airlines.