Transportation in Alaska

This article discusses transportation in the U.S. state of Alaska.

Alaska has a small population within a very large geographic area. The geographic differences mean that no single transportation strategy works for the state as a whole. Roads connect the major Southcentral population centers with Fairbanks and the Canadian border. Barges supply the communities along the coast and major rivers, and a ferry system supports the coastal communities in the south. A railroad connects the ports of Seward, Whittier, and Anchorage with the interior via Fairbanks. Many interior communities are connected by seasonal ATV trails when the weather is cold enough to freeze otherwise impassable grounds. Air travel is the critical connection between these various regions.

Alaska's climate and geography provide significant challenges to building and maintaining roads. Mountain ranges, permafrost, long distances between small population centers, and the cost of transporting materials all add to the costs and challenges of Alaska's road system. Many of the northern highways have tighter weight restrictions during spring, where axle load limits can be reduced by as much as 20% due to seasonally soft ground.

Alaska is arguably the least-connected U.S. state in terms of road transportation. Its road system covers a relatively small area of the state, linking the central population centers and the Alaska Highway, the principal route out of the state through Canada. The state capital, Juneau, is not accessible by road, which has spurred several debates over the decades about moving the capital to a city on the road system. One unique feature of the road system is the Anton Anderson Memorial Tunnel, which links the Seward Highway south of Anchorage with the relatively isolated community of Whittier. The tunnel held the title of the longest road tunnel in North America (at nearly 2.5 miles [4 km]) until completion of the 3.5-mile (5.6 km) Interstate 93 tunnel as part of the "Big Dig" project in Boston, Massachusetts. The tunnel retains the title of the longest combination road and rail tunnel in North America.

Vehicles are transported to and from many coastal communities only by boat.

The State and local boroughs maintain about 4,700 miles (7,600 km) of winter trails throughout the northern and western regions. The trails often follow paths laid out by indigenous people, and the network stretches along the coast from Norton Sound to the Beaufort Sea. Trails reach the interior along the Yukon, Koyukuk, and Kobuk rivers. In 2004, the State Department of Transportation worked with local partners to provide wayfinding in the form of tripods made of 8-foot (2.4 m) tall reflective stakes, able to be placed each season when the ground freezes enough to allow passage. It intended to place these tripods at least every 500 feet (150 m). In addition to refuge cabins maintained along the route in case of emergency, the tripods can be used for basic shelter with the addition of a tarpaulin.

Winter trails are established every winter after the ground freezes and contain three categories:

The Iditarod National Historic Trail (not to be mistaken for the race of the same name) is a network of roughly 2,400 miles (3,900 km) of trail stretching from Seward in the southeast to Nome in the northwest. The trail began as a composite of trails established by Alaskan native peoples. During the Gold Rush era from the 1890s to the 1920s, it connected a string of mines, trading posts, and settlements, for which it was declared a National Historic Trail in 1978.