North and South Satellites

Sea-Tac Was Flying High in the Seventies

By 1975, annual passenger numbers had topped six million and that meant finding more room for travelers and airplanes.

South Satellite | North Satellite | Satellite Transit System

Customs and Immigrations area, South Satellite at Sea-Tac, 1981

Sea-Tac, South Satellite in foreground

On July 1, 1973, the Airport dedicated two new satellite terminals along with an underground train system to connect them to the Main Terminal.

South Satellite

This new terminal not only reflected the surge in air travel, but also the boom in international travel. It became the departure point for northwesterners heading to Asia, Europe and beyond.

International Arrivals, Sea-Tac, 1982

It was, and still is, the place where travelers from all over the world are welcomed to the United States and the Pacific Northwest. In addition to new gates for aircraft, and amenities and waiting areas for travelers, the new satellite became home to four federal agencies: Customs, Immigration, Agriculture and Public Health.

Today this satellite serves both domestic and international airlines. All direct international flights arrive here.

North Satellite

When this 243,000-square-foot satellite opened it served just one airline: United.

North Satellite, 1980

Today, United shares the space with both Alaska and Air Canada.

North Satellite interior, 1992. Port of Seattle photo by Don Wilson.

Sea-Tac Gets a Subway

With two detached satellites poised for passengers, a transportation link was needed. The solution was the first of its kind in any U.S. airport: an underground train system.

Satellite Transit System, 1972

When the Satellite Transit System opened in 1973, it had just nine cars.

Satellite Transit System install, 1972

By 1975, the unique transit system was carrying more than one million passengers annually.

Satellite Transit System, 1970s

As it approached its 30th birthday, the STS was definitely feeling its age. A $161-million project rejuvenated it. In 2004, the STS renovation was complete with new trains, guidance and communication systems, lighting, artwork and expanded, renovated subway stations.