S-25 Berkut

The S-25, initially designated as Berkut (Russian: С-25 «Беркут»; "Berkut" means golden eagle in English) was the first operational surface-to-air missile system fielded by the Soviet Union. In was first tested at Kapustin Yar in the early 1950s, was deployed in several rings around Moscow starting in 1955 and became combat ready in June 1956. However, the system failed to detect, track, and intercept the only overflight of the Soviet capital Moscow by a Lockheed U-2 reconnaissance plane on 5 July 1956. It was only ever used defensively around Moscow. The more mobile S-75 Dvina (SA-2 Guideline) would be used in almost all other locations. Several improvements were introduced over the system's long service life. It was finally replaced by the S-300P in 1982.

The system's NATO reporting name is SA-1 Guild. S-25 is short for Systema 25, referring to the entire system of missiles, radars, and launchers. Portions of the system include the V-300 missile, R-113 and B-200 radars, and A-11/A-12 antennas for the B-200.