The good news is that a 210' zip line has been installed in a park I've been working on for 5 years. I call it my "Jesus Park" and the primary purpose of the 3/4 acre park is to host 4,5,6 graders on some Friday night overnighters. The drop is good, but not life endangering. My eight year old granddaughter took the first formal ride. In fact, she had about 5 rides before anyone else. Our son, Josh, took 3 rides. I put a bungee brake on it, so the rider doesn't propel into the tree. Fun, fun, fun!!! Will try to post some pics soon.