Aleppo is a city in Syria and serves as the capital of the Aleppo Governorate, the most populous governorate of Syria. It is Syrias largest city and one of the largest cities in the Levant region, with an estimated population of 2,098,000 residents as of 2021. Aleppo has a rich history and has been ruled by various empires and civilizations, including the Hittites, Assyrians, Arabs, Mongols, Mameluks, and Ottomans. Aleppo is also a UNESCO World Heritage site, with the Citadel, the 12th-century Great Mosque, and various 16th and 17th-century madrasas, residences, khans, and public baths forming part of the citys cohesive, unique urban fabric. In 2016, Aleppo gained international attention when Libertarian presidential nominee Gary Johnson stumbled while answering a question about the Syrian refugee crisis on MSNBC, asking "What is Aleppo?".