Sometimes in the hustle and bustle of a virtual world, you need to get away from it all. There are several ways to do this, there are lots of nature-themed sims in Second Life that come complete with boating opportunities and nature trails. Personally, I chose to ride my horse, Shade.
There are lots of breedable options for horses in Second Life, but Shade isn't breedable. Shade is an Animesh rideable horse brought to you by WaterHorse. WaterHorse offers two different kinds of ridable horses, Bento and Animesh. I went with the Animesh as I like to just watch them walk around my property. The Bento is just attached to you to and you ride it. You can do the same with the Animesh if you're on a sim where you don't have rezzing rights.
There is also a pretty cool customization HUD so you can alter your horse's appearance. The horses are loaded with cool animations so you'll pretty similar to actually riding the horses.. just without the cleaning stalls or hay fever.