Moon.
On one hand, the Moon is just a boulder flying in space, covered with craters. But on the other hand, the Moon is something much more.
Firstly, the Moon always faces Earth with the same side. This means it has another side where almost anything could be. From a secret base of a infamous Austrian artist to Bowser's castle from Mario. In the middle of the last century, however, the far side was photographed, and some of the romance dissipated.
Secondly, it glows at night. Have you ever tried walking on moonlit nights in places without light sources? You can see quite well there.
And there are also such wonderful places on the Moon as the Sea of Tranquility and the Ocean of Storms. These names paint pictures in my head of a fantasy novel about a long journey across lunar seas.
But we still need to draw a stone with craters. That's what we'll do.