Dramatic geyser eruptions are just another part of what brings more than half a million tourists to Yellowstone National Park each year.
But unlike the park's most famous geyser, Old Faithful, some of these natural wonders are quite shy.
While Old Faithful can erupt as often as once every 35 minutes, the Ear Spring geyser can go decades without activity.
The geyser finally broke its silence last month, and in a bizarre twist it brought back old gifts from Yellowstone's tourists.
"The water had just washed out under the boardwalk and had strewn trash all around."
In September, Ear Spring erupted for the first time since 2004, and for just the fourth time since 1957.
It was a powerful eruption, which fired steaming water 30 feet in the air.
But the biggest surprise of the long-awaited event came after the eruption, when park workers inspected the geyser.
"The water had just washed out under the boardwalk and had strewn trash all around," said supervisory park ranger Rebecca Roland.
All kinds of trash, from a cement block to vintage beer cans, a baby pacifier, and dozens of antique coins, were belched up out of the water.
Park officials say some the garbage dates back to the 1930s, and was probably thrown into Ear Spring by careless visitors.
More modern junk, including cigarette buts, plastic spoons, a rubber heel insert, a drinking straw, and a ball of crumpled foil were also found.
Eagle-eyed readers have also noticed what looks like a destroyed tablet device and a plastic Jazz cup (sold between 1992 and 2004) in a photo of the garbage.
Some of the garbage will be kept in Yellowstone's archives, as a nifty way to show the deep connections between humans and the park's natural springs.
But Roland says the junk is also a sad reminder of our impact on nature.
"You might think that if you toss something in a hot spring or in a geyser that it disappears, but it doesn't disappear," she said.
"It stays in that and what normally happens is you can actually plug up a feature and kill the feature. And that's happened in many places in the park."
This year, Yellowstone has seen a large number of eruptions and geyser activity, which has some concerned that a volcanic eruption is coming.
New vents spewing boiling water onto parts of the tourist boardwalk even forced officials to close sections of the Upper Geyser Basin last month.
But experts say the Geysers are connected to activity happening just a few hundred feet underground, not Yellowstone's underground volcano.
As a fair warning, throwing trash into the park's geysers is still strictly forbidden.
"Foreign objects can damage hot springs and geysers," the park said on Facebook.
"The next time Ear Spring erupts we hope it's nothing but natural rocks and water."
[H/T: Four States Homepage]