The prominent crater on the northern edge of Mare Imbrium has a diameter of 62 miles (100 km). It was just like the Mare Imbrium flooded with lava and can easily be seen by its dark ground. The walls rise between 1110 and 2200 yards (1000 and 2000 m) above the ground. When the Sun is low above the horizon, they cast a long and impressive shadow low on the walls.