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U.S. National Park Service: 3 ideas worth knowing

3 ideas from U.S. National Park Service, each explained in a minute and credited to the original work. Free on Savvy.

• The tip of the Washington Monument is capped in aluminum, once pricier than silver

  When the Washington Monument was finished in 1884, its capstone was cast from 100 ounces of pure aluminum, then a rare metal costing about $1.10 an ounce, roughly twice the price o…

  — National Park Service, The Washington Monument

• Yellowstone's biggest hot spring is rainbow-coloured because of heat-loving microbes

  Grand Prismatic Spring, the largest hot spring in the United States, gets its rings of orange, yellow and green from mats of thermophilic bacteria and archaea living at different t…

  — U.S. National Park Service, Grand Prismatic Spring

• Denali, not Everest, has the tallest base-to-peak rise of any mountain on land

  Everest's summit sits highest above sea level, but it rises from a Tibetan Plateau base already around 5,200 metres up, leaving a climb of roughly 3,600 metres. Denali's base sits …

  — U.S. National Park Service, Denali National Park & Preserve

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