Take the Sea Underground train to get to all the gates: The A, B, C, and D Concourses. The concourses are all connected and you can walk or take the train to any of them. To get to the N and S Gates, you'll have to take SEA Underground since they're not connected to other gates.
It's an underground people mover system at Seattle-Tacoma International Airport
The SEA Underground, formerly called the Satellite Transit System, is an automated people mover system operating in the Seattle-Tacoma International Airport in SeaTac, Washington, United States.
Originally opening in 1973, the SEA Underground is one of the oldest airport people mover systems in the world. It was designed to quickly transport passengers to and from the North and South Satellites, and around the airport's Main Terminal.
I found the system clean and well lit underground train transportation to your departure gates.
Multiple signs are posted all around the airport directing you to the Sea Underground train. We took the Green Line to gate C18.
The ride was very pleasant and fast. Seats appeared clean. Floors were also clean of debris.
Thank you SEA Underground! read more