Many people have set up a backyard zip line. It's not difficult to do in short distances such as a backyard and kids really love it. Ziplines for backyard space can be created with relatively low height. Some platforms are the swing set, tree house, or playground equipment.
Zip line kits offer an easy way to put up a zip line in your backyard at a reasonable price. Short, ready-to-install zip lines are perfect for the backyard or a nearby field, even a playground. They range from about 35 feet in length to 90 feet, and can be installed from tree to tree without the need for a lot of drop in elevation. The sag in the cable provides a nice drop down to the low point, slowing or stopping just short of the end. To make the zip line run a little faster tighten the cable and add just a little drop in elevation. It isn't necessary to install short zip lines on a hill. Flat backyard spaces work quite well. You can achieve a couple foot drop in elevation from start to finish simply by anchoring the end a little lower on the tree.
Many people have installed backyard zip lines. Email a video link and feature your backyard zip line project. Below are some examples: