This is most, if not all, of what you need for a zip line between two strong trees. See the book Handy Dad (ISBN-13 978-0811869584) for one way to build one. I tried to create one myself but realized that our yard only has one tree strong enough, not two. Hoping to find a good home for this!
The cable is about 70 feet long.
Materials for a zip line (Glen Rock)
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