The first capital of the Ottoman Empire, Bursa still remains a very important historic city. It is a UNESCO World Heritage Site boasting a rich historic heritage including religious monuments, mosques, tombs, and baths. Moreover, the main tourist attraction is the Yesil Mosque (Green Mosque), with its carved marble doorway which is one of the best in Anatolia. Bursa is also very well known because of the mountain Uludag which towers behind the city core and which is also a famous ski resort. People travel to Bursa to go skiing and the Uludag ski resort become a popular tourist destination in Turkey in winter. Believe it or not, Bursa is the 4th biggest city in Turkey and it once was the capital city of the Ottoman empire.