The Lightning Field by the American sculptor Walter De Maria, is a work of Land Art situated in a remote area of the high desert of southwestern New Mexico. It is comprised of 400 polished stainless steel poles installed in a grid array measuring one mile by one kilometer. The poles — five cm in diameter and averaging 7 meters in height—are spaced 70 meters apart and have solid pointed tips that define a horizontal plane. A sculpture to be walked in as well as viewed, The Lightning Field is intended to be experienced over an extended period of time, and visitors are encouraged to spend as much time as possible in it alone, especially during sunset and sunrise. In order to provide this opportunity, Dia offers overnight visits during the months of May through October.