Railroads in Georgia consist of 1,583 km (606 mi) of track (not including industrial lines). Railways serve primarily as connections to the Black Sea for inland cities like T'bilisi, Chiat'ura, Jvari, and Tkvarcheli. Highways in 2002 totaled an estimated 33,900 km (21,066 mi), of which 29,500 km (18,331 mi) were paved. The maritime fleet of 64 ships (of 1,000 GRT or over) had a capacity of 210,629 GRT (288,565 DWT) in 2002. Batumi and Poti are the principal Black Sea ports. Georgia has 31 airports, 16 of which have paved runways. Its only international airport is Tbilisi which is capable of handling 1,000–1,200 passengers per hour. In 2001 there were 782,000 aircraft departures, and 110,800 passengers were carried on scheduled domestic and international airline flights.