Sergei Korolev initially promoted the Soyuz A-B-V circumlunar complex (7K-9K-11K) concept (also known as L1) in which a two-man craft Soyuz 7K would rendezvous with other components (9K and 11K) in Earth orbit to assemble a lunar excursion vehicle, the components being delivered by the proven R-7 rocket.

The 7K would have been equipped with cameras and sensors to study the lunar surface during the flyby, at a distance of 1,000 to 20,000 km from the Moon's surface.

Total flight time would have been 7 to 8 days.

The 7K series is a direct descendant of this original proposal.

The list below shows proposed, flown (in bold) and military (in italic) Soyuz versions.