Transport in Portugal is diversified. Portugal has a 68,732 km (42,708 mi) network of roads, of which almost 3,000 km (1,864 mi) are part of a 44 motorways system. Brisa is the largest highway management concessionaire. With 89,015 km2, Continental Portugal has 4 international airports located near Lisbon, Porto, Faro and Beja. The national railway system service is provided by Comboios de Portugal. The major seaports are located in Leixões, Aveiro, Figueira da Foz, Lisbon, Setúbal, Sines and Faro.