Sir Bani Yas (Arabic: صير بنى ياس‎) is a natural island located 170 km (110 mi) southwest of Abu Dhabi, the capital of the United Arab Emirates. It lies 9 km (5.6 mi) offshore from Jebel Dhanna, which serves as a crossing point to other islands such as Dalma. Sir Bani Yas is 17.5 km (10.9 mi) from north to south and 9 km (5.6 mi) from east to west, making it the largest natural island in the United Arab Emirates. Located just off the shore of the Western region of Abu Dhabi, Sir Bani Yas island was originally home to Arabia's largest wildlife reserve. Spanning over 87 km² (34 sq mi), the reserve was established in 1977 by Sheikh Zayed Bin Sultan Al Nahyan. Thanks to decades of conservation work and ecological investment, it is now home to thousands of large free-roaming animals and several million trees and plants.