OJSC "Aeroflot — Russian Airlines" (Russian: «Аэрофлот — Российские авиалинии»), commonly known as Aeroflot (Russian: Аэрофлот, translation: "air fleet"), is the largest airline in Russia, based on passengers carried per year. Aeroflot, headquartered in Moscow, is one of the oldest airlines in the world, tracing its history back to 1923. The airline operates domestic and international passenger services to 97 cities in 48 countries, mainly from Sheremetyevo International Airport serving Moscow. During the Soviet era, Aeroflot was the Soviet national airline and the largest airline in the world. Since the dissolution of the USSR, Aeroflot has been transformed from a state-run enterprise into a semi-privatised airline which ranks amongst the most profitable in the world. Aeroflot is still considered the de facto national airline of Russia.