The Blue Crush actress, 30, wore two custom Oscar de la Renta dresses for the big day, including a strapless ivory gown with a sweeping eight-foot-long, 16-foot-wide train for the ceremony. Michael, meanwhile, looked dapper in a three-piece charcoal Brooks Brothers suit.
The beautiful ceremony took place on a mountain top at The Ranch at Rock Creek in Montana, overlooking the lush hay meadows and rolling foothills typical of the region. Surrounded by 50-75 of their closest friends and family, Kate and Michael exchanged vows they had penned themselves.
The newlyweds decided on the romantic destination for its privacy and rustic old-school charm. Michael also feels an attachment for Montana as his paternal side hails from there.
Guests received welcome tote bags upon their arrival, which included a special, handwritten message from the lovebirds and items that had a personal meaning to them, such as locally bottled huckleberry soda.
Friends and family were also given Polaroid cameras and asked to take photographs of the happy couple, and complete the captions with the phrase, "Love is... ".
After the ceremony, the wedding party made their way down the mountaintop to Granite Lodge, where a gargantuan meal of local food was served. Kate changed into her second bespoke Oscar de la Renta gown — a floral embroidered tulle dress, with an illusion neckline and scalloped cap sleeves.
The joyous festivities carried on after dinner with dancing in the historic Silver Dollar Saloon and a long night of partying.
Guests stayed at the ranch for the four-day celebration and had the chance to throw themselves into the fun activities Montana offered, including horse riding, fishing, hiking and archery.
Kate and Michael, who met on the set of Big Sur in 2011, got engaged when the film director proposed during a trip to South Korea.
"I never even dated my husband-to-be," the actress has previously revealed. "He said to me after just a few weeks, before we were even together, 'I'm going to marry you.' He just knew."