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yellowstone
wyoming
united
states
tourist
archival
historical
america
travel
vintage
70s
retro
seventy
seventies
american
old
1970s
tourism
tour
mammoth
hot
springs
geyser
travertine
terrace
steam
caldera
colorful
national
park
geothermal
basin
montana
calcium
flowing
limestone
microorganisms
geology
carbonate
touristic
nature
water
usa
spring
wilderness
thermal
pool
wildlife