Allison Williams, age 27, tied the knot with longtime boyfriend and entrepreneur, Ricky Van Veen, age 34. It was a star-studded ranch wedding on Saturday, September 19, a rep exclusively told Us Weekly.

The two sweethearts exchange their "I dos" in front of close family and friends, the rep tells Us.

The guest list included Katy Perry, John Mayer, Bruce Springteen, Bee Shaffer, Andy Cohen Tom Hanks and his wife, Rita Wilson (who plays Williams' mother on Girls), and Williams' costar Lena Dunham.

The exclusive outdoor wedding was a weeklong event. A source informed Us Weekly, the guests at the wedding head towards the venue on Thursday, September 17.

Started with a casual party, and then a dinner rehearsal with the soon to be newlywed was celebrated on Friday.

On the wedding day, Allison was dazzling in a handmade couture gown designed by Oscar de la Renta.

It was truly a month of love when Williams and Van Veen announced their engagement last February after dating for three years. The longtime sweethearts are the co-founder of the website College Humor.

After the announcement, the couple kept secret their wedding plans since the actress' father, Brian Williams, who is an anchor in NBC Nightly News, was facing criticism for embellishing news stories.

In one instance, he made false claims about an assignment in Iraq; he was then suspended and reassigned to MSNBC.

The Girls star has been sharing about her plans to start a family in the near future. "I'd love to be a mom - and not have to bring my kids into my trailer," she told Glamour. Our congratulations go with the newlyweds!