Fingal's Cave is on Staffa, an island near Scotland.
The island, like many of the Inner Hebrides, is made of volcanic rock.
The vertical lines seen in the photograph were formed when hot lava cooled.
The shrinking lava produced a columnar pattern.
These volcanic rocks date from around 50 to 60 million years ago.
At that time, the North Atlantic was starting to form, with Europe beginning to split from North America.