A pony ride on a sandy beach used to be a traditional part of the British summer holiday for children. I don’t think the ponies ever looked anything like this however, The beaches probably weren’t as nice either.
If you hunt around for images of femdom and ponyboys you’ll find a lot of silly posed shots. This vintage shot is particularly bad, but representative of the type. The image below was one of the few I found that looked like she was genuinely going for a ride rather than simply posing for the camera. I also have to admire her ponies dedication. That full face hood must be incredibly hot.
I’m afraid I haven’t a reference for the creator of this image. Please leave a comment if you can help me attribute it.