The Filyovskaya line, or Line 4 and 4A, formerly the Arbatsko-Filyovskaya line is a line of the Moscow Metro. Chronologically the sixth to open, it connects the major western districts of Dorogomilovo and Fili along with the Moscow-City with the city centre. At present it has 13 stations and is 14.9 kilometres (9.3 mi) long.

The Moscow Metro is a metro system serving the Russian capital of Moscow as well as the neighbouring cities of Krasnogorsk, Reutov, Lyubertsy and Kotelniki in Moscow Oblast. Opened in 1935 with one 11-kilometre (6.8 mi) line and 13 stations, it was the first underground railway system in the Soviet Union.