Abstract: Trolley systems and associated rails and tracks are described, the trolleys having an integrated brake system that can be adapted to slow or stop the trolley based on various control inputs (internal or external). The track system may be formed from either or both of a series of tensioned cables or tracks that are interconnected with transition system and the trolleys described, able to transition between track systems. The track system may be fitted with additional braking elements to govern motion of the trolley along a track system. Additionally, the track may be fitted with other elements that provide an external input into the trolley to modify the braking operation of the trolley.