A hole in the side of a hill or under the ground is known as Cave.
A large hole in the side of a hill or mountain or in the ground is called a cavern or a cave. These natural formations can be created through various processes like erosion, weathering, or volcanic activity.
A "canyon" is a large hole on the side of a hill or mountain or on the ground. Canyons are typically formed by the erosion of water or wind over time, creating deep valleys with steep sides.
A crater - I don't think there are any other answers possible!
Foxes live in an under ground burrow called a den. It is much like a rabbits hole with two openings for escaping. But a fox's den can be in the side of a hill, mountain, or cliff.
cave
The word you are looking for is "cave." A cave is a hollow opening or natural underground space that is typically large and found in hills, mountains, or the ground.
A Cave
Holes underground are called caves. They could be in the side of a hill. The places where bears live are called dens. A bear's den may be in a cave but often is not.
there is a little hole right under the hood next to the driver side door
Ah, what a wonderful question! That sounds like a beautiful thing to paint. A large hole in the ground or side of a hill or mountain is called a "canyon" or "cave." It's nature's way of creating stunning landscapes for us to admire and find inspiration in. Just imagine the colors and textures you could use to capture the beauty of such a magnificent sight on your canvas.
give it a name for the location, woody [in the woods] down&out [vally] hiview I call mine the hole, in a hill side,
in the tank. There is an access hole under the rear seat on drivers side