The stockpile is an invulnerable storage building for raw materials. It has to be placed in the beginning of the game before doing anything else. It can be extended by building adjacent blocks of additional stockpiles in close proximits, increasing effective storage capacity. The stockpile provides a pathway for workers and troops.
A stockpile can contain a large number and variety of resources. Each stack size depends on the type of the stored material. When clicked on, the "resource summary" panel is shown with a detailed list of available resources. If the market is built, the resource can be clicked on to trade as well.
Up to three stockpile buildings can be placed during a game. Deleting a stockpile will remove all stored contents in it.