On the cool webpage called the art of manliness , we found this suggestion for a great outdoor workout: “The playground workout”. From the article:
When you get creative, and, well, think outside the box, you can get a great, intense, completely free bout of exercise from your surroundings. If you head into the woods, tree branches and rocks can become your new equipment and weights. But even a more developed piece of landscape offers a whole host of opportunities: the playground.
You can find exercise demo video and workout description here: