Seattle is a state of the UCAS on the Pacific Coast separated from the rest of the country by the Native American Nations. Seattle itself is located in the middle of Salish-Shidhe, its access to the Pacific Ocean passing through Salish-Shidhe waters in the Puget Sound and Juan de Fuca Strait. However the provisions of the Treaty of Denver give Seattle unlimited access to the passage. It is sometimes called Seattle State or Seattle Metroplex when there is a need to distinguish it from Seattle City (which is itself more commonly designed as Seattle Downtown).
Seattle has a population of just over 4 million official (plus around 2 million unregistered) inhabitants and covers 3,992 square kilometers. It is the most densely populated UCAS state with about 750 inhabitants/km², and the second smallest UCAS state after Rhode Island.