Lava channel on a ridge on the Moon
The 300 kilometers long Rima Ariadaeus.
Seen here is part of the 300 kilometers long lava channel, a rille, on the Moon called Rima Ariadaeus.
Unlike sinuous (curved) rilles which are volcanic in nature, linear (straight) rilles like Rima Ariadaeus are formed differently. The linear rille of Rima Ariadaeus is thought to have been formed when a section of the Moon's crust sank down between two volumes of rock. The following illustration makes it clear.
In the featured image above, the rille is seen to cross the ridge from above it, which suggests the rille is younger than the ridge. The rille also cuts off some craters meaning it is younger than those craters as well. Finally, the rille itself has few craters on it. All of these suggest that Rima Ariadaeus is a relatively young lunar feature.