What stunning creatures!
I've seen plenty of Garter Snakes and Ribbon Snakes, and several different species of them. However, I'm not sure I've ever encountered the Red-sided Gartersnake (Thamnophis sirtalis parietalis) in my travels thus far. While cleaning up a property in Missouri recently, I encountered two, and they were amazing.
Garter snakes are a common, nonvenomous snake that can be found across much of North America, I grew up catching them in my native Wisconsin. We've found a number of them on our homestead too, just never any that had this amazing red color on them. These photos were taken right when I caught them. I hope to share some better photos later. Enjoy!