The raising of animals for food and other products

A border created by a physical feature, such as a mountain, river, or strait

A center where cultures developed and from which ideas and traditions spread outward

A system of writing that used wedge-shaped symbols pressed into clay tablets

An underground canal first built by the ancient Persians

Large, pyramid-shaped temples made of mud-brick, created by the Sumerians

A ban on trade

A tributary that leads to a larger river

A wetland typically covered with grasses

Wide, grassy plains of Central Asia