Matthew McConaughey and his "True Detective" co-star, Woody Harrelson, bonded over their shared love of the open water while on a paddleboard during a group vacation in Dubrovnik, Croatia.

McConaughey, 52, wore a pair of grey swim trunks, and sat in the front of the soft-top board, while Harrelson paddled in the back wearing neon blue and green striped shorts.

Both men went shirtless for the outdoor adventure in the Adriatic Sea, with McConaughey opting for a backwards hat and sunglasses. 

His wife of 10 years, Camila Alves, dropped by to hang out with the guys, and paddled out in her own inflatable kayak.

Matthew McConaughey and Woody Harrelson shared a paddleboard in the water on Croatia holiday

Matthew McConaughey and Woody Harrelson, bonded on the open water while on a paddleboard during a group vacation in Dubrovnik, Croatia. (Splash News)

Woody Harrelson and Matthew McConaughey paddleboarded in Croatia

McConaughey, 52, wore a pair of grey swim trunks, and sat in the front of the soft-top board. (Splash News)

Harrelson and McConaughey — who are both from Texas — have worked together on various projects dating back more than 20 years in the entertainment industry, beginning with "EDtv" in 1999. 

They reunited in 2008 for the comedy "Surfer, Dude," and became a crime-fighting pair on the critically acclaimed HBO crime series, "True Detective." 

Matthew shared a sweet snap of his best friend to Instagram two years ago after they jumped into the water. "Brothers from nother mothers?" he captioned the shot.

MATTHEW MCCONAUGHEY PLEADS FOR RESPONSIBLE GUN OWNERSHIP IN EMOTIONAL WHITE HOUSE PRESS BRIEFING

Matthew McConaughey and Woody Harrelson enjoyed some time in the sun together on vacation.

Woody Harrelson paddled in the back of the long board wearing neon blue and green striped shorts. (Splash News)

Harrelson and McConaughey enjoyed time together on vacation

Matthew and Woody looked content while out in the middle of the ocean together on a family retreat. (Splash News)

During an appearance on "The Ellen DeGeneres Show" in 2019, Harrelson admitted he has an annual tradition of "friendship tours" with his buddies every year.

At the time, he had shared a photo on Instagram with McConaughey, Chris Rock, Sasha Baron Cohen and his wife Isla Fisher at Bono’s South of France home.

"I take a 'friendship tour' pretty much every year," he told DeGeneres. "I thought about calling it a 'bender where I leech off my rich friends,' but I thought, 'No, you know — friendship tour, better.’"

He added: "You just go, stay at their house, drink oblivious. Great."

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Camila Alves kayaks to her husband at sea

Matthew McConaughey's wife of 10 years, Camila Alves, dropped by to hang out with the guys, and paddled out in her own inflatable kayak. (Splash News)

Harrelson and wife Laura Louie have been married for 13 years and have three children.

Baron Cohen and Fisher were also recently seen on the annual "friendship tour" in Europe, where Rock joined in on the fun with his new girlfriend, Lake Bell.

Rock is preparing for a joint stand-up comedy show with Dave Chappelle later this year.

The two comedians will appear on-stage together on Sept. 3 at The O2 in London, Live Nation announced. Tickets for the event went on sale June 10, and due to high demand, another date was added for Sept. 4.

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