Here's "the world's largest captive geyser" (???) at Geyser Park in Soda Springs. I guess it's considered "captive" because it's controlled by a timer now, which is set to allow the geyser to spout once an hour on the hour. I arrived just at spouting time, and had to hastily abandon my lunch sack in the middle of the parking lot to rush over and take pictures.
I brought some water home with me. The bottle is in the fridge and when I open it, it gives a very satisfying "psssht"!