Mare Serenitatis
Montes Haemus is a mountain range that forms the southwestern edge of the Mare Serenitatis basin on the Moon. They form a less prominent mirror image of the Montes Apenninus range to the west, and curve up to nearly join at the northern end. The eastern edge terminates with the Promontorium Archerusia, to the northwest of the crater Plinius. This end reaches a gap where the Mare Serenitatis to the north joins the Mare Tranquillitatis to the south.