A century ago, we might have had a better idea, but since 1918, this territory has been known as Guam. Yesterday, Governor Camacho signed an order changing the name back to Guahan for territorial-government purposes, but the U.S. Congress must agree for the name change to have full legal effect.
To answer the original question, by the way, Guam (Guahana) is the largest of the Mariana Islands (and as such, neighboring the world's deepest ocean trench). It is in the far western Pacific Ocean, about 6,000 miles from San Francisco.
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