Workers at Yellowstone National Park (a vast geothermal wilderness in the western United States) have removed a record 20,100 items of rubbish from the park's hydrothermal areas so far in 2026, surpassing all previous totals. The haul includes 280 hats, 36 pairs of sunglasses, six Invisalign retainers, eight toy racing cars, and more than $18 in mixed international currencies tossed in by visitors treating the hot springs as wishing wells. Park officials warn that any foreign material — whether blown in by Yellowstone's strong winds or dropped deliberately — can permanently damage the fragile geothermal features by clogging water channels or introducing polluting chemicals, as famously happened to the Morning Glory Pool, which turned colour from accumulated rubbish in the early twentieth century.