Celebrity Pony Pics ... Happy National Horse Day!

It's National Horse Day, y'all ... so pony up to shots of celebs givin' some love to these gorgeous equines!!!

Bella Hadid and Kendall Jenner were cheesin' for the camera next to their four-legged friends, and Alicia Keys snapped a pic while riding horseback in the water -- a big bucket list adventure for some people.

Selma Blair got up close and personal with a horse ... one that seemed a bit more interested in getting some food than posing for the photo!

LSU gymnast Olivia Dunne didn't go for the pommel horse -- that's more of a men's gymnastics thing -- but she did take some photos on top of a real horse that's rockin' a beautiful white mane!