Eyewitnesses tell TMZ ... the make-out couple was staying at the Montage Resort in Laguna Beach. After leaving the pool Tuesday, lips locked, they hit the sand for more action ... drawing attention from beachgoers within eyesight.
Kourtney was straddling Travis ... his hands pulling her jeans down a bit, and sucking faces like there's no tomorrow! Things got so intense, one nearby family -- with kids -- walked up to them, although it's unclear what was said, but probably something along the lines of "get a room!"
After their sandy sesh, the two ran down to the ocean for more fun ... and to cool off.
Beachside fun is nothing new for the couple ... we've seen them hand-in-hand at beaches a bunch. In fact, Travis even popped the big question right on the sand back in October of 2021. No word yet on a wedding date.