Hikers in the Greater Yellowstone high country. The power of the outback is most potent when humans allow themselves to have a sensual experience devoid of ringing phones, pings and ear buds. While phones come in handy for taking photos, do the images really need to be instantly posted on social media while you're still on the mountain and, just as bad, identifying quiet places and invited the masses to overwhelm them? Photo courtesy Jacob W. Frank/NPS