By the third millennium, the most important of its city-states was the Sumerian city of Ur.

One of the most famous Sumerian cities was Ur.

Sumerian cities were surrounded by defensive walls.

He discovered the ancient Sumerian city of Uruk in 1849.

What makes one Sumerian city better than another one?

Ur was an important Sumerian city that is now known as Tell el-Mukayyar.

It is named after the ancient Sumerian city of Uruk.

The great walls surrounding the Sumerian city of Uruk gained a widespread reputation.

Nippur was one of the most ancient of all the Sumerian cities.

Thus, each Sumerian city became a city-state, independent of the others and protective of its independence.