| January 2, 2013

Congratulations are in order for Hugh Hefner. On New Year's Eve, the Playboy founder married Crystal Harris, his girlfriend of nearly four years. 

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But this isn't Hef's first marriage, and certainly not his first long-term relationship. At 86 years old, the men's magazine mogul has had more than his share of ladies — many of which he dated concurrently. And with the exception of his first wife Mildred Williams, all of Hefner's most publicized relationships were with Playboy models (and almost exclusively with blondes, as we learned).

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Check out some of the ladies who have won Hef's heart.

Crystal Harris

Hefner's current girl, new wife Crystal Harris, was Playboy's Playmate of the Month in December 2009. A year later, she and Hefner were engaged. Five days before their initial wedding date of June 18, 2011, Harris called off the nuptials. The ex-couple reconciled and eventually became engaged again on December 1, 2012.

Kristina and Karissa Shannon

Twin sisters Kristina and Karissa Shannon, aka Miss July and Miss August of 2009, were also Hefner's girlfriends during the early stages of his relationship with Harris. (All three also appeared on the last season of "The Girls Next Door," the E! reality series focusing on Hefner's girlfriends in the Playboy Mansion.) More recently, they were contestants on the UK reality show "Celebrity Big Brother," and eventually lost the competition on the final episode.

Holly Madison

Former Playboy model and original "Girls Next Door" star Holly Madison was involved with Hefner from 2003 through 2008. Afterward, Madison starred in a short-lived reality series called "Holly's World," which chronicled her life in Las Vegas. She is currently expecting her first child with partner Pasquale Rotella.

Kendra Wilkinson and Bridget Marquardt

While dating Holly Madison, Hefner was also seeing Playboy models Kendra Wilkinson and Bridget Marquardt. (The three were the original subjects of the E! reality series "The Girls Next Door.") Wilkinson left the Playboy Mansion to star in her own series titled "Kendra" (and later, "Kendra On Top") with husband and football player Hank Baskett. After Marquardt left, she briefly hosted "Bridget's Sexiest Beaches" on the Travel Channel.

Associated Press
Sandy, Mandy and Brande

Hefner had several girlfriends (sometimes up to six or seven the same time) between the years of 1998 and 2005, including Playboy models Sandy Bentley and her twin sister Mandy Bentley, as well as April 2000 Playmate of the Month Brande Roderick.

Associated Press
Kimberley Conrad

Between the years 1989 and 2010, Hugh Hefner was technically married to Kimberley Conrad, 1988's Playmate of the Month for January. They separated after nine years but remained married for 11 more. "I would've been happy to divorce her when we separated," said Hefner, but he claims that Conrad wanted to stay married until the youngest of their two boys, Marston and Cooper, turned 18.

Associated Press
Barbi Benton

Actress and model Barbi Benton (center) was involved with Hugh Hefner from 1969 through the mid-70s. They began their relationship after appearing together on Hefner's television show "Playboy After Dark." He asked the 19-year-old on a date, and she is rumored to have said, "I've never dated anyone over the age of 24." Hefner replied, "That's okay, neither have I."