Michael Douglas and Catherine Zeta-Jones [1] were all smiles when they were spotted enjoying a stunning vacation in the French Riviera on Thursday. The couple of more than 16 years, who recently returned to the spot where they got engaged [2], looked so in love as they held hands before soaking up the sun while making their way to board a luxury yacht. Missing from the trip, however, were the couple's two beautiful children, Carys and Dylan [3]. Keep reading to see more of their getaway, then check out other Hollywood couples who have been together the longest [4].