The United Arab Emirates (UAE) is located in the southern corner of the Arabian Peninsula. It is a federation of seven independent emirates. The largest emirate is Abu Dhabi, the others (Ajman, the smallest one, Dubai, Fujairah, Ras al-Khaimah, Sharjah and Umm al-Qaiwain) are known as the Northern States. The UAE is bordered by the Persian Gulf to the north, Saudi Arabia to the south and west, Qatar to the northwest, and Oman and the Gulf of Oman to the east. Desert landscape with vast sand dunes is the the leading type of the terrain. The world's largest sand dunes are located east of Aradah. The Al Hazar Mountains are situated in the northern part of the country. Because of the subtropical climate the United Arab Emirates is usually called the country of year-round sun. Along the coast the weather is hot and humid, in other parts - it is hot and dry.