On Monday, Yellowstone National Park closed all entrances due to flooding and rockslides.
"Extremely hazardous conditions" followed "unprecedented" rain in the northern part of the park, according to a news release.
Yellowstone National Park will be closed to inbound visitor traffic on Tuesday, June 14, and Wednesday, June 15, at a minimum.
Gardiner, Montana, and the park were also without power.
The riverbank gave way beneath several park structures, according to Gardiner firefighter Austin King.
He woke up at 1 a.m. on Monday to the sound of his pager beeping, and hasn't stopped since.
It's the highest river I've ever seen," said King Monday evening. "There are people living here 64 years - they've never seen it."
All of its occupants escaped with minimal possessions, King said, and only a few wood planks remained at the bunkhouse.
Medical emergencies will have to be helicoptered out of Gardiner, he said.
National Weather Service meteorologist Cory Mottice says the flooding wouldn't have been this bad without the snow.