Most pictures here are from Garner State park, you do need reservations due to covid. The Frio river starts around Leaky Texas where east and west frio river meet, the river does have high water in some places and others it's really low to non exciting, you pretty much have to drive around to find a good spot. The water color is more blue/turquoise when the sun is super shiny! You can find free spots to access the river thru crossings also something you need to look thru maps to find. Best to rent a lodge or cabing around Leaky thru Garner park for best access to the river. The views driving around are beautiful. Also cell service is not the best unless you have att, so take a map just in case. Happy traveling!