Mare Vaporum 13.0°N, 3.5°E

Mare Vaporum (‘Sea of Vapours’) has an irregular, rounded shape with a diameter of 240 km and a lava-covered surface that amounts to about 55 000 km2. Mare Vaporum lies to the southeast of the Apennine mountains. In the south, Mare Vaporum merges, without any visible boundary, into the lava plain that is Sinus Medii. The southwestern and southeastern boundaries between Mare Vaporum and the highland regions are marked by secondary impacts from the great Imbrium impact (forming part of the Imbrium Sculpture). To the northwest lie Sinus Fidei and Lacus Felicitatis on the borders with the Apennine mountains.

Lacus Felicitatis 19.0°N, 5.0°E

Lacus Felicitatis (‘Lake of Happiness’) is a smaller, irregularly shaped lava area of only about 90 km in extent. It lies southeast of the crater Conon and east of Rima Conon. Scientists believe that they have found evidence here that part of this area still exhibits volcanic activity in the form of outgassing. Proof came in 2006 from a small area, named Ina, that lies on the southeastern edge of Lacus Felicitatis. Ina is a semicircular depression (shaped somewhat like the heel of a shoe), whose coordinates are 18.6°N, 5.3°E, and with a diameter of only about 3 km (about 1.5 arcseconds) and a depth of about 30 m. Even in large amateur telescopes the area is only partially visible.

Menelaus 16.3°N, 16.0°E

Menelaus is another young, very prominent crater, 26 km in diameter, with a sharp crater rim and central peaks.