The Hajar Mountains stretch through the border between Dubai and Oman. They are located 100km (62 miles) south of Dubai city, along the border with Oman. The range is divided into the Eastern Hajar Mountains and Western Hajar Mountains. These mountains are very rugged, with idyllic villages, rivers and valleys. The Al Hajar Mountain (stone mountains) range is the highest in eastern Arabia, forming a spectacular wall of mountains that rise from the surrounding deserts. The Hajar Mountains constitute the world's most extensive surface exposure of ophiolites. For this reason they are of tremendous interest to geologists. Highlights are the wadis (dry river beds), which often collect rain or flood water and offer the chance to cool off, and the hill town of Hatta, which has been recreated as a mountain oasis.