Historic thermal pool misused by visitors as laundry attraction

Handkerchief Pool in Yellowstone National Park was long a curiosity among visitors, who would place handkerchiefs and similar cloth items into its waters to watch them disappear beneath the surface and mysteriously reappear—a phenomenon that made it one of the park's more unusual attractions.

The pool's distinctive hydrothermal activity came to an end in 1926 when a log became lodged within it, disrupting the circulation patterns that created the vanishing and reappearing effect visitors had come to expect.

Following the obstruction, park authorities undertook a cleanup operation in 1929 to assess and remove accumulated debris. The effort yielded significant findings: maintenance crews extracted approximately 1.5 bushels of material deposited by visitors over the years, including more than 100 hairpins, numerous coins, and even a horseshoe.

The discovery underscored how visitor interaction, though often well-intentioned, had left its mark on the natural feature. The incident became a notable example of how even popular thermal attractions required careful management to preserve their geological and environmental integrity.