A hot ticket for the past two years, Washington’s popular National Museum of African American History and Culture did away with its ticket requirement Monday, the first day of a month-long experiment with no-pass weekday admission.

Visitors began lining up before 8 a.m. on the last day of the holiday weekend, which was the first of the museum’s September Walk-up Weekdays. Several hundred were waiting when the doors to the Smithsonian’s newest venue opened at 10 a.m.

“It’s truly a blessing to be here,” said Melva Thornton, 68, of Charlotte, one of the first in the queue. On vacation in D.C., Thornton arrived at 7:45 a.m. to guarantee her entry. She had tried to get passes online in the past but had had no success. She was delighted to wait without worry as she watched a multicultural, multi-age crowd form behind her.

“I’m glad to see it’s a mixed group. I hope it brings the country together,” she said.

Since its historic opening on Sept. 24, 2016, the museum at the corner of the Mall near the Washington Monument has attracted big crowds. More than 4.3 million people have visited, making it one of the city’s most popular museums. The timed passes — available at no charge in advance or at 6:30 a.m. for same-day entry — have been used to prevent long lines at the entrance and keep the galleries from getting too crowded.

Jaclyn DeVore was among the hundreds who had arrived early Monday because they were uncertain how difficult it would be to get in. The Harlem resident and her children Lawrence, 11, Lukas, 10, and Lauren, 8, spent about 35 minutes waiting for the doors to open. “I figured everyone would have the same idea,” DeVore said. It didn’t take long for the family to snake through the shaded queue and get through security. By 10:30 a.m., visitors could go right in.

This month’s Walk-up Weekdays is the latest test of no-pass entry as museum officials try to balance access for everyone who seeks it with optimal conditions for enjoying the galleries. For more than a year, small numbers of visitors have been allowed to enter without passes on weekday afternoons, if capacity allows. In April and May, the museum debuted Walk-up Wednesdays and saw an increased number of visitors. Passes are still required on weekends, when attendance rises and there’s greater use of advance passes.

This month’s Walk-up Weekdays is the latest effort toward the elimination of passes.

“We’re going to analyze the data, to try to understand the patterns, see if there are patterns,” Associate Director of External Affairs Beverly Morgan-Welch said. “We’re hopeful it will be a successful experiment.”

Many in line had tried to visit previously but were unsuccessful. Others, like Craig and Loretta Stuart of Delanco, N.J., had visited with passes earlier this weekend, but learned about the new policy and decided to return before going home Monday afternoon.

“We stayed until closing but we were only able to see about three-quarters of the [underground] galleries,” said Craig Stuart, who said he and his wife walked right in around 11 a.m.

“I hope it works,” he said of the new policy. “It’s a good problem to have, that there are still so many people trying to get in.”

Others were surprised by the new rules. Jonathan Acevedo, 31, signed onto the museum’s website to get same-day passes early Monday morning for him and Elizabeth Hutto. The pair are visiting from Orlando and had tried to go Sunday but couldn’t get tickets. They arrived at 10 a.m. Monday, when the museum opened, and were walking in the door at 10:22. “Like the lines at Disney,” Acevedo said.

The relaxed entry rules meant Aditi Ghatlia was able to see the popular museum with her father, Naresh, who was visiting this weekend. Self-described history buffs, the father and daughter were pleased it took only 15 minutes to get in.

“I’ve read a lot about the museum, and this was a good time to come,” said Naresh Ghatlia, who had spent 35 hours on three flights from Bangalore, India, to Washington to spend time with his daughter. Aditi works in the city and had made her first visit at the summer solstice, when the African American Museum was open late.

“I loved it but I had to rush,” she said. “I wanted to come back and take my time.”