This invention is a gravity powered Dual Cable Zipline Trolley Transfer System comprising, a dual cable zipline trolley and dual cable zipline transfer unit which work in conjunction of each other. The trolley comprises tandem wheels that traverse over the dual cables and are pivoted in the center to allow the trolley to pass smoothly over the transfer unit, which is suspended on support structures. Unlike the traditional zipline which has a path between two stations, this system is designed to allow the participant to travel in a continuous uninterrupted path without the need to detach from one cable to another in order to sustain the journey beyond the station. The transfer unit is lengthened to create curves both horizontal and vertical. This invention eliminates the menacing sag in the cable that occurs over distance.