San Francisco de Quito is the capital and the largest city of Ecuador, and at an elevation of 2,850 meters (9,350 ft) above sea level, it is the second-highest official capital city in the world, after La Paz, and the one which is closest to the equator. The historic center of Quito has one of the largest, least-altered and best-preserved historic centers in the Americas. A monument and museum marking the general location of the equator is known locally as la Mitad del Mundo (The middle of the World).
Climate, Quito has a subtropical highland climate. Because of its elevation and proximity to the equator, Quito has a fairly constant cool climate. The average afternoon high temperature is 21.4 °C (70.5 °F) with an average night-time low of 9.8 °C (49.6 °F). The annual average temperature is 15.6 °C (60.1 °F).
The Mariscal Sucre International Airport serves as the city's principal airport for passenger travel and freight. The airport is located 18 kilometers (11 mi) east of the city's center in the Tababela parish.
Quito Metro, 23 kilometers (14 mi) metro subway system is under construction. Phase One, begun in 2013, entailed the construction of stations at La Magdalena and El Labrador. Phase Two, begun in 2016, involves 13 more stations, a depot, and sub-systems. The project is expected to carry 400,000 passengers per day and is expected to be operating in 2020.