Katie Holmes and Jamie Foxx are continuing to spend time together in Miami
*PREMIUM EXCLUSIVE* Katie Holmes and boyfriend Jamie Foxx ride jet skis in Miami on New Year's Eve weekend
Credit: Splash News/MEGA

Making a splash!

As Katie Holmes and Jamie Foxx continued to spend time together on their romantic Miami vacation, the pair were spotted riding around on a pair of Jet Skis on Saturday.

Holmes, 40, and Foxx, 51 — who have mostly kept their four-and-half-year romance away from the public eye — had an adventurous day on Biscayne Bay aboard red and blue jet skis.

Riding in front of Foxx, Holmes was seen smiling as the duo took in the sights.

One day earlier, the pair were spotted relaxing on a private yacht, with Holmes rocking a black bikini and Foxx sporting a simple white t-shirt.

Katie Holmes and Jaime Foxx
| Credit: Kevin Mazur/Getty Images

The couple’s Florida fun comes weeks after they were seen celebrating the actress’ 40th birthday in New York City.

During their Dec. 18 outing, the couple were joined by Holmes’ mother, Kathleen A. Stothers-Holmes, and stopped by popular dessert destination Serendipity 3, where they enjoyed a strawberry sundae and frozen hot chocolates.

Katie was all smiles,” a source told PEOPLE. “She and Jamie were flirty.”

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The actors were first seen dancing together in 2013 in the Hamptons, a year after Holmes and ex-husband Tom Cruise, 56, called it quits.

Though both have had busy schedules in the last few months, they’ve made efforts to see each other regularly. In November, the two spent time together in New Orleans, where she was filming The Secret and he was working on an untitled sci-fi thriller for Netflix. Foxx visited Holmes on her set and they also enjoyed a romantic dinner date at Restaurant R’evolution in the city’s French Quarter.

“Their relationship seems so much more serious this year,” a source told PEOPLE in this week’s issue, on newsstands now. “Katie and Jamie keep having public dates, and although they try to not be photographed together, they are clearly not as concerned about keeping their relationship private.”

“Katie always acts super-excited and giddy when Jamie is around,” added an insider. “They are very cute together.”