This is not a moonscape. The western half of the Arabian peninsula contains not only large expanses of sand and gravel, but extensive lava fields known as haraat (harrat for a named field). One such field is the 14,000-sq km (5,400 sq mi) Harrat Khaybar, located approximately 137 km (85 mi) to the northeast of the city of Al Madinah (Medina). The volcanic field was formed by eruptions over the past 5 million years; the most recent of which took place about A.D. 600-700. Image courtesy of NASA.