Aviation in Alaska has a central importance In the vast, lightly populated state with severe weather issues. The short highway system links a few major population centers; railroads are of even lesser importance. Ocean ports, islands and river towns are served by ocean-going vessels. Air service makes up the rest. Air service by "bush pilots" to the Interior and western Alaska, as well as the Aleutian Islands, allowed for the influx of settlers, the year-round contact of villages with the state's larger cities and services, mail and supplies, and rapid transportation of people and goods throughout the state.