Ladder

A ladder is any stackable structure that features a ladder on its side, allowing engineers to climb vertically.

It may refer to:
 * Conveyor Pole Stackable
 * Pipeline Pole Stackable
 * Hyper Tube Support Stackable
 * Storage Container
 * Industrial Storage Container
 * Fluid Buffer
 * Industrial Fluid Buffer

Buildings that are non-stackable, but feature a tall ladder:
 * Lookout Tower
 * Radar Tower

Beside these, many factory buildings also have a ladder but are not stackable, such as Smelters and Miners.