Elevated decks strung between fixed points across sloped or forested terrain, independent of any single tower.
Not every site needs a tower to get people off the ground. Where terrain is sloped, or a route needs to move guests along a canopy edge rather than straight up through it, a suspended walkway does the job a single mast can't: a continuous elevated path, strung between fixed anchor points, that follows the shape of the land instead of standing apart from it.
The design questions are different from a tower's, too. A walkway lives with sustained lateral sway and repeated foot traffic along its whole length rather than a concentrated load at one platform, and the anchor points at each end carry the tension the whole span depends on. It is a structural cousin of a tower, built from the same steel-and-cable vocabulary, aimed at a horizontal route instead of a vertical climb.