ABC News June 29, 2015

Taylor Swift Posts Fun Pic With Calvin Harris, Joe Jonas and Gigi Hadid

WATCH: Taylor Swift's Private Boat Tour With Calvin Harris and Joe Jonas

Taylor Swift posted a fun picture on Sunday, spending time with her rumored new man Calvin Harris and another rumored couple -- Joe Jonas and Gigi Hadid. Karlie Kloss was also on the boat ride through London.

Swift, 25, who famously dated Jonas back in 2008, also joked about Kloss, 22, being the group's tour guide.

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"Little known fact: Karlie is secretly an unofficial historian/London tour guide. Kind of," she wrote.

Jonas, 25, also posted a pic captioned, "#IMONABOAT."

Swift was in London over the weekend for the British Summertime festival.

She posted a pic from the show with thousands upon thousands of excited fans in attendance.

"The crowd of 65,000 that went on forever, as far as I could see in each direction... Hyde Park," she wrote.

Three weeks ago, Swift made her social debut with Harris, posting a picture of the couple hanging together by the pool.

Then Harris, 31, himself tweeted a week ago, "I just played a gig inside a giant owl and my girl just changed the entire music industry what a day."