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