File:111-SC-10262 - U.S. transport unloading horses and mules by chutes, Bassens Docks, Bordeaux, France. - NARA - 55180857 (avril 1918).jpg - Wikimedia Commons
Permission to Come Aboard — Four Surviving WW2 U-Boats You Can Actually Visit - MilitaryHistoryNow.com
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Canals - Transportation (U.S. National Park Service)
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Permission to Come Aboard — Four Surviving WW2 U-Boats You Can Actually Visit - MilitaryHistoryNow.com
Retrieval of sunken boats at John Day Dam underway - oregonlive.com