Peru has 69,941 km of roads, 10% of which are tarmac. The main roads are along the coast over 2,800 km, and the Inca Trail, which links Lima to the interior of the country. Considerable projects to improve the road network are underway. The railway network covers 1,876 km, 1,576 km of which have a 1,435 m gauge and 300 km have a 0.914 m gauge. The state of the network is poor. The port of Lima (Callao) is the biggest port in Peru. Peru has 8,600 km of waterways (tributaries of the Amazon and 300 km on Lake Titicaca). Air transport is often the only means to reach jungle areas inaccessible by road or the fastest way to reach some Andean populations. Secondary airports are those of Cuzco, Tacna, Arequipa, Iquitos, Ayacucho, Chiclao, Piura and Trujillo. Small airline companies offer regular flights between the country's cities. In 1994, 54 million tons of goods were transported by air.