Queen's Laundry Bath House in Yellowstone National Park stands as a small unfinished ruin beside the Queen's Laundry thermal feature in the Lower Geyser Basin. Built in 1881 under superintendent Philetus Norris, it was planned as a simple public bath house at a rare thermal site where water was cool enough for bathing, but construction stopped before completion and Norris's successor, Patrick H. Conger, did not resume it. Despite continuing deterioration and encroachment by hot springs deposits, it survived because it is the only remaining structure from Yellowstone's early civilian management and is often regarded as possibly the oldest extant park visitor structure in the National Park Service system.

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Mammoth, Wyoming · USA