An artesian well is a “pumpless” well. Water courses through porous rock, in a seemingly astounding feat of defying gravity. This is made possible by the pressure that accumulates between the rock layers. In an effort to relieve pressure and achieve equilibrium, the rock pushes up the water, which winds its way to the top. Once it reaches open air, the pressure is relieved.
For thousands of generations people have relied on Artesian wells for water. Unlike traditional wells, the Artesian well provides water that is cold (since it is not exposed to direct sunlight) clean. The rock acted as natural filters and percolators, trapping contaminants as the water passed through it. In fact, water from Artesian wells was much safer than river water. The upward pumping also saved people from the trouble of having to haul buckets of heavy water with rough rope. In ancient times, people accessed Artesian wells by hitting a rod with a sharpened tip with a hammer.
The water source of an Artesian well is called an aquifer. It is actually a layer of limestone, sandstone or any other permeable rock that sucks in the water from an inlet path. This is usually located at a high location, like a mountain top. Very often the water comes from melting snow or the high levels of precipitation at those levels.
The layer of permeable stone is surrounded by two layers of impermeable stone like clay soil or rock, causing the high levels of pressure that push the water to the surface. This is the same principle behind natural springs, though springs usually flow through a gap caused by an external event caused by something like an earthquake.
Artesian wells exist all over the earth.