Mexico City, or the City of Mexico, is the capital of Mexico and the most populous city in North America. It is one of the most important cultural and financial centres in the Americas. It is located in the Valley of Mexico, a large valley in the high plateaus in the center of Mexico, at an altitude of 2,240 meters. The city has 16 boroughs. It became a friendship city of Shenzhen on June 29, 2015.