COUNTY CLARE, Ireland -- Think of Ireland and you're likely to picture lush rolling green hills. But in the country's northwestern region, a strange silvery-gray landscape extends for about 100 square miles (250 square kilometers). Known as the Burren, this moonlike terrain is the result of karstification, a process by which erosion creates an exposed-limestone topography dotted by fissures, sinks, ravines and underground streams.
It's a landscape of ever-changing light that dances over soft hills and sharp cliffs, and the absolute silence is broken only by the sound of the wind blowing through low scrub. Ancient castles, Neolithic tombs and dramatic caves dot the landscape, making the Burren at times feel like a living -- and slightly haunting -- storybook.
Roughly 350 million years ago, the Burren -- which comes from the Irish word "boíreann," meaning "stony place" -- was under the ocean. To this day you can still find fossils and shells embedded in the rock.
The waters eventually receded, leaving behind sedimentary rock, and two ice ages brought glaciers through the region that carved the limestone into its present-day form.
About the eerie landscape, British general Edmund Ludlow once said that it's "a country where there is not enough water to drown a man, wood enough to hang one, nor earth enough to bury him...and yet their cattle are very fat; for the grass growing in turfs of earth, of 2 or 3 foot square, that lie between the rocks, which are of limestone, is very sweet and nourishing."
In fact, though on first glance the Burren looks like a wasteland of stone, the longer you walk along its ancient paths, the more you realize just how much plant life and bird species the area supports.
I had the great fortune to spend the entire month of April in the Burren learning its secrets both above and below ground. Take a look at the gallery I've put together to learn even more about this most remarkable region.