Just after 12 p.m. on December 12, 2012, Eric Gaudette and Stacy Northrop were married atop the East Chop Lighthouse.

A handful of friends and family joined them, including long-time friends Barry Stone and Rebecca Cohen.

“They told us three weeks ago ‘We’re getting married on 12-12-12,’” said Ms. Cohen. “Eric said, ‘Barry, you’re going to be the best man, and Rebecca, you’re going to stand in as my mother.’”

Wedded bliss can't miss on 12-12-12. — Katie Ruppel

Mr. Gaudette said his wife worried all week that the celebration would be rained out, but the rather impromptu December wedding proved her wrong. Around 12:12 p.m., justice of the peace Ken DeBettencourt married the couple at the top of the lighthouse with clear blue skies as the backdrop.

Skimming through the calendar two months ago, Ms. Northrop realized it was 10-11-12.

“It would have been a perfect day to get married,” she said. So we thought, “What’s the next best day?”

And so the century’s last sequential date it was.

“And I thought he’d be able to remember it,” Ms. Northrop joked.

A few bystanders stood below with their necks craned, including friend Melanie Godek, who married last year on 11-11-11.

“It will be 100 years until it happens again,” said Mrs. Godek of the quirky numerical day.

Mr. Gaudette and Ms. Northrop met on a blind date two-and-a-half years ago, although both have been living on the Island for more than two decades.

“I found a soulmate,” said Mr. Gaudette. “When you find someone you love, you know it.”