BETHEL, N.Y. — Tie-dyed pilgrims and white-haired Woodstock festival veterans converged at the generation-defining site to celebrate its 50th anniversary, while Arlo Guthrie came back to sing — what else? — “The Times They Are a-Changin’.”

Bethel Woods Center for the Arts is hosting a series of events Thursday through Sunday at the bucolic 1969 concert site, 80 miles northwest of New York City.

Guthrie, an original Woodstock performer, was scheduled to play an evening set atop the famous hill, but said he also wanted to play at least one song near where the 1969 stage was located. Picking up a guitar, he sang the Bob Dylan classic for a group of reporters gathered on the grass under the wilting afternoon sun.

“It was a great time,” Guthrie told reporters, his long white hair flowing from a straw hat. “For me, the Woodstock festival was a celebratory end of an era. It was not the beginning of anything. It was the end of something, and it was an end of a very turbulent time that was also very wonderful.”

An estimated 400,000 people showed up for the original festival on upstate New York farmland Aug. 15-18, 1969.

There won’t be overcrowding and chaos this time. Visitors need event tickets and travel passes to drive to the site through the weekend. But the site was buzzing by the afternoon, with people stopping by the on-site museum and the monument near the stage area.

“This is like a pilgrimage. Coming back to the holy land,” said Glenn Radman, a 67-year-old New Milford, Conn., resident stopping by the monument with his friend.

Radman was at the festival 50 years ago, as was 75-year-old Roger Dennis, an Ithaca, N.Y., resident who was making his first visit since that famous weekend.

“I was here 50 years ago right on this day, and it was one of the most powerful experiences of my life. And I just had to be back here,” Dennis said, standing by the monument.

Dennis went to the concert with his brother and turned 26 years old that Sunday. His brother died years ago, which made the visit Thursday a bit melancholy.

“But the memories the energies of this festival were just unbelievable,” he said. “And I feel that.”

Access to the field is usually open, but Bethel Woods is setting restrictions this weekend to avoid a repeat of the chaos that engulfed the site in 1969.

Bethel Woods is hosting a long weekend of events featuring separate shows by festival veterans like Carlos Santana and John Fogerty.

Michael Hill is an Associated Press writer.