The Cliffs of Moher are located on the southwestern edge of the Burren in County Clare. They are 120 meters above the Atlantic Ocean at Hag's Head, and reach 214 meters at their height just north of O'Briens Tower, eight kilometers to the north. The cliffs take their name from an old fort called Moher that once stood on Hag's Head, the southermost point of the cliffs. There are estimated to be 30,000 seabirds nesting on the cliffs, representing more than twenty species. The cliffs are one of the most popular tourist destinations in Ireland, topping the list of attractions in 2006 with one million visitors.