Streets in this plat that were not extensions of already existing ones, such as Commercial Street, were named after letters of the alphabet, American cities, American states, prominent local politicians, and places in Washington.
Those places in Washington were Chelan, Duwamish, Kitsap, Klickitat, Queets, Quilcene, Quileute, Quinault, Spokane, Vashon, Wenatchee, and Whatcom, many (though not all) of which were themselves named after Native American groups or people. (Chelan, Duwamish, Klickitat, and Spokane are the only street names that remain.) In this particular case, we have the Klickitat River, a tributary of the Columbia in south central Washington, itself named for the Klickitat people.
Klickitat Avenue SW begins at 16th Avenue SW and goes around ⅖ of a mile southeast to SW Manning Street, all on Harbor Island.
Born and raised in Seattle, Benjamin Donguk Lukoff had his interest in local history kindled at the age of six, when his father bought him settler granddaughter Sophie Frye Bass’s Pig-Tail Days in Old Seattle at the gift shop of the Museum of History and Industry. He studied English, Russian, and linguistics at the University of Washington, and went on to earn his master’s in English linguistics from University College London. His book of rephotography, Seattle Then and Now, was published in 2010. An updated version came out in 2015.