Pull the brass eyelet clasp and a concertina of civic pride unfolds — this remarkable fold-out souvenir mail card for Walla Walla, Washington Territory cascades into a miniature accordion book of black-and-white photographic views including the 4th U.S. Cavalry on parade at Fort Walla Walla, an alfalfa field in April with a lone horseman, the I.O.O.F. (Odd Fellows) Hall, and a panoramic view of Puget Sound at Anacortes. The outer cover presents Puget Sound, Anacortes as the "postcard" face, with the handwritten notation "Walla Walla" in a period hand. Published by the Patent Mailing Souvenir Co. of New York (No. 441) and classed as "Printed Matter / Souvenir Mail Card" with one-cent postage to all countries, this format was patented and marketed aggressively in the early 1900s. The military image of the 4th Cavalry is the standout frame — the 4th U.S. Cavalry was stationed at Fort Walla Walla from the 1890s into the early 1900s, and photographs of the regiment on parade are eagerly sought by military postal historians.