|Feature on||The Moon|
|Feature type||Montes (mountain range)|
|Lunar coordinates||8° S, 28° W|
|Dimensions||Length: 189 km|
Width: varying up to 50 km
|Bounding features||Mare Cognitum, Oceanus Procellarum|
|Notes||The lunar sea known as Mare Cognitum is contained within a walled basin, but the walls of that basin are now largely obscured. The range of Montes Riphaeus is a small remnant of the ancient wall structure on the Sea's northwestern edge.|
A broad range of mountains in the southwestern quadrant of the Moon's visible face. The Montes Riphaeus mark a part of the southeastern margins of the vast Oceanus Procellarum, standing at the point where that Ocean of Storms meets Mare Cognitum, the Known Sea. These mountains take their name from the Riphaean or Riphean Mountains that were said to be the source of the north wind in Greek mythology.
The Riphaean range runs for nearly 200km in an approximately north-south direction, a remnant of the ancient wall that once bounded Mare Cognitum. The mountains are divided into numerous ridges, and can reach 50km across at their widest points. At their northern end, the range divides into several wide valleys, whose smooth floors show that they were at one time filled by lava flows. To the west, some 50km from the feet of the nearest foothills, lies the prominent rayed crater known as Euclides.