Which city's metro includes the Sokolnicheskaya Line?

The city whose metro includes the Sokolnicheskaya Line is Moscow.

The Sokolnicheskaya Line is Line 1 of the Moscow Metro, traditionally shown in red on system maps. It runs across Moscow on a southwest–northeast axis and is operated by Moskovsky Metropoliten. The line takes its name from Sokolniki, the northeastern district and park associated with its original terminus.

It opened on May 15, 1935, as part of the first stage of the Moscow Metro and is the network’s oldest line. Its early stations helped establish the architectural style for which the Moscow Metro became famous, although the earliest sections are more restrained than later Stalin-era stations. The line has since been extended far beyond its original route.

The name can cause confusion because “Sokolnicheskaya” is transliterated from Russian in several ways. It is not a line of the Minsk, Kyiv, or Saint Petersburg metros. Moscow’s other metro lines have their own names and colors, but this historic first line remains particularly associated with the city’s subway origins.