Serena Williams - Lead
Credit: Jim Spellman/WireImage

There's no doubt that Serena Williams's bikini body is red hot. The tennis star isn't shy about showing off her killer physique, and she did so once again over the weekend while enjoying some fun in the sun with a group of pals. Williams took to Instagram to document her inner-tubing excursion on the San Marcos River in Texas, where she hit the water with Arrow actor Colton Haynes and friend Val Vogt.

"Core memories with @valgabond @coltonlhaynes love you guys," she captioned a photo of the trio. Haynes also shared the same snap, and wrote: "Cheers to more core memories wit these 2 @serenawilliams @valgabond :) What an epic adventure."

"Adventures and belly laughs all weekend long. Love these guys. #corememories," Vogt said alongside a second 'gram of the besties. We just have one question: Can we come along next time?