Yellowstone's south loop, where the Old Faithful geyser and the colorful Grand Prismatic Spring are, reopened Wednesday, but the north loop remains closed, officials said.
The damage from the floods, mudslides and rock slides, which occurred after heavy rain combined with snowmelt last weekend, was most pronounced in the northern part of the park.
The emergency prompted the park to close on June 13. Around 10,000 visitors were moved out of the 2.2 million-acre park. No injuries or deaths were reported.
Fewer than 5,000 vehicles entered the south loop Wednesday. Normally the number would be more than 10,000, the National Park Service said in a statement.
The park put an “alternating license plate system” in place to restrict the number of vehicles and prevent the open parts of the park from being overwhelmed.
Among the thousands of visitors Wednesday were Lonnie and Graham Macmillan of Vancouver, British Columbia, who tried to go last week but were turned away because the park was closed.
“The whole purpose of our trip was to come here,” Lonnie Macmillan told The Associated Press. “We weren’t going to go home until we got here.”
The northern loop is expected to open in about two weeks, park officials said this week.
The National Park Service on Monday announced $50 million in funding to kick-start recovery efforts. It has said it expects that visitor access will be restored to about 80% of the park by July 4.
The flooding also hit Montana communities, including the Yellowstone gateway town of Gardiner. Businesses that depend on visitors have been left uncertain about the season.
Yellowstone, which is mostly in Wyoming but also in parts of Idaho and Montana, celebrated its 150th anniversary this year. President Ulysses S. Grant signed the law establishing it on March 1, 1872.
Last year the park had 4.9 million visits, according to the park service.