Building an Outdoor Structure Print E-mail

At my local park, we have a fitness path. It is about half a mile long and has a variety of different events set up for doing different exercises. The best one is pullup station. It has three bars at different heights. One of them is perfect for pullups, another is about 12' high and is great for hanging Elite Rings. The whole thing is solid because of the three bars. It would be very easy to make this with adjustable height bars, or to have a rotating bar or bars of different thickness. It would be a fairly simple project to build one in your backyard, or in your local park (with permission from your city).
Here are some pictures of the station.