Prince Harry at Rolling Stones' Festival Performance, Enjoys Late Night

Prince Harry attended the Glastonbury music festival alongside other high-profile Brits such as Kate Moss and Florence Welch over the weekend.

The prince was spotted at the main event of the festival on Saturday; a performance by the Rolling Stones.

Furthermore, the 28-year-old royal attended Gastonbury with his rumored girlfriend Cressida Bonas, according to People magazine.

Despite attending the publicized music festival, Harry was able to slip by photographers unnoticed until the very end.

The music event also attracted model Cara Delevingne and Sam Branson, and following the Rolling Stones' performance, the prince enjoyed a very late night at the festival.

"I recommended he should go on into the night, because the nightlife is what Glastonbury is all about," said the festival's organizer Michael Eavis to Daily Mail. "I told him to get his taxi driver to come back at five o'clock in the morning, and do you know what? He lasted until four in the morning."

The U.K.'s biggest music festival was a chance for Harry to enjoy not only the Rolling Stones, but also some of today's top trance-style music at the fest's various dance clubs.

"His friends were all having a great time," Eavis added. "He didn't want to make a formal thing of being here."

Celebrity attendees also included Sienna Miller and Alexa Chung, who were given their own VIP area where they enjoyed the Stones' two-hour performance.

"Musically, they were absolutely brilliant," Eavis said of the legendary rock group. "Mick Jagger's energy leading that band with such a passion and so much style, he was absolutely amazing."

According to other reports, Prince Harry was casually clad as he enjoyed the festival's various nightlife activities.

"Harry was well up for it," an onlooker told The Sun U.K. "He was dancing in a grey trilby and a white T-shirt, with two security guards close by. They just let him get on with it."

Alternately, Bonas was photographed earlier in the say wearing denim overalls paired with white sneakers while eating French fries.

Meanwhile, Prince Harry along with the rest of the world is awaiting the arrival of his brother's first child.

Harry's older brother Prince William and wife Kate Middleton are expecting the arrival of the royal baby within the next couple of weeks.