The stars came out to celebrate Sir Elton John over the weekend.

The iconic singer turned 70 on March 25 and celebrated with a celeb-studded birthday bash on Saturday in his honor. Hosted by Rob Lowe at Red Studios in Los Angeles, the guest list included Neil Patrick Harris, Jon Hamm, Ryan Phillippe, Heidi Klum, Katy Perry, Sascha Baron Cohen and Isla Fisher and Dakota Johnson, according to reports.

In addition to the A-listers in attendance, several celebrities who couldn't make it out to celebrate the Rocket Man sent their good wishes via video clips—Prince Harry, Ellen DeGeneres, Bono, and David Beckham all submitted virtual birthday messages to the singer—thus proving that the singer is one of the most popular men in entertainment. Of course, it never hurts attendance when your reputation for throwing an epic bash precedes itself. His yearly Oscars viewing party is one of the hottest tickets in town, and he's thrown some extravagant birthday parties before. Saturday night's party certainly didn't disappoint.

The evening featured several musical performances from Roseanne Cash and Ryan Adams—but the highlight of the night came when Lady Gaga took the stage with Stevie Wonder to serenade John with Wonder's rendition of "Happy Birthday."

In addition to the performances in his honor, John took time during the celebration to pay tribute to his husband, David Furnish, saying that he helped him turn his life around from his previous partying ways, according to People. The evening, which also paid tribute to John's 50-year writing partnership with Bernie Taupin, benefited both the Elton John AIDS Foundation and the Hammer Museum at UCLA.

Related: Inside Elton John's Modernist, Man Ray-Filled Photo Collection

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