Treasures are guarded by one or more treasure guardians which are usually wild animals or outlaws. The player must kill the treasure guardian or guardians to enable the ability for a Explorer or Settler to collect the treasure.
- Note: Alain Magnan, the only mounted explorer in Age of Empires III, is unable to collect treasures, while the Explorer in the expansions can.
In the The Asian Dynasties, there are Water Treasures that can be collected only by naval units in a body of water. A peculiar set of treasures all belonging to an individual known as "El Pollo Guapo" (Spanish for The Handsome Chicken) can be found across various maps, most of which bequeath benefits to cavalry units and Explorers.
"The New World was full of hazards for even the most prepared colonists. Some settlers arrived with shockingly little in the way of supplies. Carving a niche out of the rugged wilderness was only the beginning. They faced harsh weather, bold predators, starvation, and disease. Native Americans ranged from helpful to hostile, depending on how much and what kind of contact they had already had with other European settlers. Many colonies were simply abandoned, like Popham colony in Maine; its settlers returned to England after only a year. Some, like Roanoke, vanished completely, and no one knows what happened."