Transport in Afghanistan is done mostly by road, rail and air. Much of the nation's road network was built in the mid-20th century but left to ruin during the last two decades of that century due to war and political turmoil. Officials of the current Islamic Emirate have continued to improve the national highways, roads, and bridges. In 2008, there were about 700,000 vehicles registered in Kabul. At least 1,314 traffic collisions were reported in 2022. Landlocked Afghanistan has no seaports, but the Amu River, which forms part of the nation's border with Turkmenistan, Uzbekistan and Tajikistan, does have substantial traffic. Rebuilding and expanding its airports, roads, rail network, and land ports has led to rapid economic growth in recent years. There are 46 airports in Afghanistan as of 2021. Road Most major highways were asphalted around the mid-20th century with assistance from the United States and the Soviet Union. The Soviets built a highway and tunnel through the Salang pass in the 1960s, connecting northern and eastern Afghanistan. A highway connecting the principal cities of Herat, Mazar-i-Sharif, Lashkar Gah, Kandahar, Ghazni, Kabul and Jalalabad, with links to highways in neighboring Pakistan originally formed the primary road system of Afghanistan. As of 2017, Afghanistan had 17,903 kilometers of paved roads and 17,000 kilometers of unpaved roads, for an approximate total road system of 34,903 kilometers. Traffic in Afghanistan is right hand. In 2008, about 731,607 vehicles were registered in Kabul. At least 1,314 traffic collisions were reported in December 2022. Many vehicles in the country are driven without registration plates. The Afghan government passed a law banning the import of cars older than 10 years. Toyota Corolla has been the most widely used vehicle in the country since the mid-1990s. Afghanistan recently began manufacturing its own cars for domestic consumers. Long distant road journeys are made in private cars, vans, trucks and buses. Many of the national roads are in need of serious repair due to damage caused by overloaded trucks. For this reason, tourists, business people and the upper class prefer using airline service for long distant travels. The national roads can also be dangerous due to accidents and lack of security forces. Highways The highway system is currently going through a reconstruction phase. Most of the regional roads are also being repaired or improved. For the last 30 years, the poor state of the Afghan transportation and communication