One of the most intriguing nations on the Arabian Peninsula, Oman is known for its lovely palm-edged beaches, green wadis (oasis), spectacular waterfalls, rugged mountains, and a unique cultural and architectural heritage. The major tourist attractions in Oman include Batinah Coast - famous for its stunning fort towns of Rustaq, Barka and Nakhal; Muscat - famous for Sultan’s Palace and the 16th century Portuguese forts; Samail - famous for its exceptional scenic beauty and architecture; Salalah - famous for its lovely beaches and ruins; Sur - 6th century town famous for its winding streets and old buildings; and Bahla - an ancient town with 7 miles of defensive walls (a World Heritage Site). Other attractions include the 7th century Jabrin Castle, Sohar Fort, Wadi Shab Waterfall, Majlis al-Jhinn (the world’s second-largest cave) and Jebel Akhdar.