A ladder is a small tool that weighs 5 kilograms. Ladders are collapsible and can be folded down into a compact form for transportation, easily capable of being stored inside a Bridges cargo case. Initially, a ladder can be up to 10 meters in length when fully extended, but can be upgraded which allows ladders to be extended even further.
Typically, ladders are used by people when traversing the world, specifically porters, such as Sam. It allows him to climb steep slopes and overcome other obstructions, and can act as a makeshift bridge when laid horizontally, allowing him to cross crevasses and rivers.
Once Sam places a ladder somewhere in the world, that ladder will then become available for other porters to use when making their own deliveries.