Ashley Olsen and boyfriend Richard Sachs vacation together in St. Barts

Ashley Olsen and Richard Sachs have taken their relationship to the next level.

The new couple celebrated their first holiday together over the weekend while on vacation in St. Barts.

WATCH: Mary-Kate and Ashley Olsen Show Off Bikini Bodies, Go Makeup-Free in France

Olsen, 30, sported a Bob Dylan tee and Nike sweatpants while out and about with her 58-year-old boyfriend, who showed off his tan in a pair of black gym shorts.

Splash News

WATCH: Mary-Kate and Ashley Olsen Reunite With Sister Elizabeth in Fierce, Floor-Length Outfits

According to an eyewitness, Olsen and Sachs spent a week at the art dealer's island villa, keeping a low-profile throughout their trip. The two went for daily romantic walks on hills near the villa, where they were seen talking, listening to music and flirting.

Olsen and Sachs were first spotted together earlier this month, showing major PDA during a New York Nicks vs. Brooklyn Nets game at Madison Square Garden in New York City.

See more photos of Mary-Kate and Ashley Olsen through the years:

The two definitely appear to be moving fast, as Sachs has already met Olsen's twin sister, Mary-Kate. The couple attended the basketball game with Mary-Kate and her husband, 47-year-old Olivier Sarkozy.

WATCH: Mary-Kate and Ashley Olsen Turn 30! Look Back at Their Rise From Child Stars to Billionaire Fashion Designers

See more in the video below.