PSAP provides the vital link between the Port of Grays Harbor and the national rail freight network. Centrally located between Seattle and Portland and unburdened by daily traffic jams of urban areas, companies gain efficient and cost-effective highway access via the four-lane highway from Interstate 5 or rail service provided by PSAP. A continuous rail loop throughout the marine terminal complex allows the free flow of cargo in and out of the facility. The rail loop is designed to handle and store unit-trains as well as smaller sets of rail cars.