Seen here is part of the volcanic mountain range Montes Carpatus, the full range stretching 361 km across the Moon.
Mountains in the range Montes Carpatus, imaged by NASA's Lunar Reconnaissance Orbiter (LRO). Source: LROC blog
Montes Carpatus forms the southern border of the Mare Imbrium, to its east lies the previously featured Montes Apenninus. Montes Carpatus formed ~3.8 to 3.9 billion years ago when the basin of Mare Imbrium was excavated by a large asteroid-sized impact. The impact uplifted nearby crustal material to form the arc-shaped mountain range.
The 361 km mountain range Montes Carpatus, imaged by NASA's Lunar Reconnaissance Orbiter (LRO). Seen below it is the famous Copernicus crater. Source: NASA on Wikipedia
The dark (low albedo) material seen littered across the landscape is proof of volcanic activity. These volcanic rocks formed when lava that originated from the melted mantle erupted about 3 billion years ago.
Volcanic landscapes like Montes Carpatus are a direct entry point into the Moon's internal structure. Such exposed internal lunar material on the surface are viable to study with future lunar landers.