Several of Tobia's adventure operators have built zip line networks on the steep slopes above the Río Negro canyon, and the setting makes for some genuinely impressive lines. The longest runs cross the valley floor hundreds of metres below, with views of the river, the canyon walls and the patchwork of forest and farmland stretching toward the horizon. It is the kind of scenery that makes you glad for the mandatory pause at each platform.
The canopy courses are typically structured as a series of connected lines rather than a single ride, so you move through the forest from anchor point to anchor point, occasionally rappelling or crossing a suspension bridge between segments. The whole circuit takes an hour to ninety minutes depending on the operator and how many lines are included. No experience is required; guides clip you in at each station and the hardware is standard descender-and-pulley equipment used at operations across Colombia.
Zip lines work well as a complement to a rafting trip — the two activities use different parts of the body, so combining them in a single day leaves you pleasantly tired rather than wrecked. Most package deals in Tobia assume you will do both.