John Travolta and 6 Other Celebrity Wedding Crashers

Hold on to your loved ones! Celebrities may just crash your wedding.

John Travolta is latest to make headlines for such a cameo. After running into an engaged couple at a bar the night before their big day, the Hollywood legend actually showed up to help celebrate their vows!

A friend of the groom's first shared the sighting — and snapshots — online.

"My friend ran into John Travolta the night before his wedding, and he shows up the next day," the friend explained.

In one pic, Travolta posed with the happy couple while flashing a thumbs-up sign. In another, he managed to wedge himself smack into the middle of the entire wedding party.

The iconic thesp looked as thrilled as anyone to be part of the main event, though he needs to be called out for showing up in jeans, a tee shirt, and a backwards baseball hat. Seriously, did Kelly really let him leave the house like that?

[Related: Celebrities Who've Officiated Weddings]

The beaming bride and groom didn't seem to mind, however, as they flashed bright smiles and mugged with their arms thrown around the star.

But Travolta is hardly the first celebrity to crash a wedding.

Robin Williams: Back in the day (and by "the day" we mean 1977), Travolta and his bestie Williams crashed a wedding at his neighbor's house in Santa Barbara. Keep in mind, this was before the actors were the icons they are now, which means they had to crash without their fame to get them through the door.

"We were having fun, starting to relax … when we saw there was a wedding next door," Travolta revealed. "We figured we'd crash it."

Conan O'Brien: Earlier this year, the late-night host dropped in on a wedding at the Four Seasons in Atlanta. In his defense, Conan had been invited ... via Twitter. One of the bridesmaids got wind that the ginger-haired star was staying at the hotel and tweeted him an invite. Not only did he show up, he even photo-bombed a few shots with the newlyweds on the dance floor!

[Related: Stars Who Waited for Their Wedding Night]

Bill Clinton: The former President did a quick drive-by during a couple's wedding at the Castlemartyr Resort in Cork, Ireland. He happened to be in town for an Irish-American philanthropy group, but when he saw the newlyweds, he walked right over and introduced himself.

Taylor Swift: Back when the country crooner was still dating Conor Kennedy, she showed up uninvited to the wedding of Liam Kerr and Kyle Kennedy at Boston's Fairmont Copley Plaza.

What's more, when the mother of the bride asked Taylor to leave (so as not to distract the attention from her daughter), the mogul reportedly refused.

Meryl Streep: Some stars are still able crash with class. When the Oscar-winning actress was in England shooting "The Iron Lady," she took a break to make a quick appearance at a nearby wedding. They were so thrilled that the star even sent them autographed photos of herself scrawled with messages of congratulations after the fact — so much better than a toaster.

LeBron James: When an about-to-be-married couple spotted the NBA standout in their hotel's courtyard after they had just taken their first look, he jumped at the chance to pose for some truly memorable photos.

The moral of the story? Celebrity crashers are great ... unless they're Taylor Swift.

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