FLAGSTAFF, Ariz. – Grand Canyon National Park has surpassed its visitation record for the second year in a row.

The Arizona Daily Sun reported that the park announced Monday that it had received its 6 millionth visitor, a 9 percent increase over the 5,520,736 visitors from 2015. The park believes its traffic is up this year because the National Park Service is celebrating its centennial and has increased marketing for the event.

Last year was also record-breaking for the park: 2015 marked the first time more than 5 million people visited the park in a year.

The Grand Canyon hit the 4-million-visitor mark in 1992.

The 6 millionth visitors were the Johnson family from Las Vegas, who were at the Grand Canyon for the first time.