or medical school. The University of Alaska has attempted to combat this by offering partial four-year scholarships to the top 10% of Alaska high school graduates, via the Alaska Scholars Program. Beginning in 1998, schools in rural Alaska must have at least 10 students to retain funding from the state, and campuses not meeting the number close. This was due to the loss in oil revenues that previously propped up smaller rural schools. In 2015, there was a proposal to raise that minimum to 25, but legislators in the state largely did not agree. Transportation Roads Alaska has few road connections compared to the rest of the U.S. The state's road system, covering 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, only a car ferry; this has spurred debate over decades about moving the capital to a city on the road system, or building a road connection from Haines. The western part of Alaska has no road system connecting the communities with the rest of Alaska. The Interstate Highways in Alaska consists of a total of . One unique feature of the Alaska Highway system is the Anton Anderson Memorial Tunnel, an active Alaska Railroad tunnel recently upgraded to provide a paved roadway link with the isolated community of Whittier on Prince William Sound to the Seward Highway about southeast of Anchorage at Portage. At , the tunnel was the longest road tunnel in North America until 2007. The tunnel is the longest combination road and rail tunnel in North America. Rail Built around 1915, the Alaska Railroad (ARR) played a key role in the development of Alaska through the 20th century. It links north Pacific shipping through providing critical infrastructure with tracks that run from Seward to Interior Alaska by way of South Central Alaska, passing through Anchorage, Eklutna, Wasilla, Talkeetna, Denali, and Fairbanks, with spurs to Whittier, Palmer and North Pole. The cities, towns, villages, and region served by ARR tracks are known statewide as "The Railbelt". In recent years, the ever-improving paved highway system began to eclipse the railroad's importance in Alaska's economy. The railroad played a vital role in Alaska's development, moving freight into Alaska while transporting natural resources southward, such as coal from the Usibelli coal mine near Healy