New York City is a world capital in every sense of the word—it's a cultural and economic powerhouse, and arguably the most influential city on the planet. But it wasn't always this way, as the following cities once dominated the world around them.
DjenneDjenno
In the flood lands of the Niger delta
people have been building houses and other structures with clay for centuries.
The town of DjenneDjenno is made entirely out of clay. It was inhabited as far
back as 250 BC, and became an important link in the transSaharan gold trade(跨撒哈拉黄金交易). Constructed on hills called " toguere", the city managed to escape the marshy(沼泽 
) landscape and annual floods produced by the rainy season. DjenneDjenno is believed to be one of the earliest settlements in the subSaharan region, and is considered by some to be "the typical African City".
Archeological evidence shows us a continuous human presence in the area up until the 14th century AD, when people moved to the nearby town of Djenne, founded in the 11th century. Further evidence points out that even before the city's construction, the Bozo people were growing wild rice in the region. In the 13th century AD, with King Koumboro's conversion to Islam, its palace transformed into a mosque.
Carthage
Legend has it that Carthage was founded by Queen Dido of the Phoenicians. She fled the city of Tyre located in presentday Lebanon in order to escape the hatred of her brother Pygmalion, who was her rival to the throne. Along with a group of settlers, she traveled a great distance by sea and landed in North Africa, where she met King Iarbas. He offered to give them land in order to build a settlement, but no bigger than the surface covered by the hide(牛皮) of an ox. They cleverly cut the hide into thin strips and were able to enclose a fairly large area of land. On this land, the mighty city of Carthage was built.
These stories are most likely just that, but the fact that the Phoenicians built the city around 760 BC is true. Located in such a good position—in the middle of the Mediterranean, close to Sicily, Sardinia and Corsica, and a pretty good distance from Egypt—helped make Carthage a leading trade center and military power. The population soon reached half a million citizens and, in order to house them all, buildings were all built five or six stories tall. Carthage was the first city in ancient times to have a centralized sewage system, linking all buildings within the city walls. The most notable of structures among the ruins was the " Thophet", which is believed to be an altar(圣坛) for child sacrifice.
Tenochtitlan
Tenochtitlan was the capital city of the Aztec Empire. It was built on an island surrounded by Lake Texcoco deep inside the jungles of Central America. By the time the Spanish conquerors were aware of its existence, the population was around 200，000. This was a city very different from what the Europeans were used to. Founded in 1325 AD, the Aztec capital was joined to the mainland by three causeways(堤道). It was laid out in straight street grids and had enormous pyramids at its center, which were surrounded by the skulls of the dead and ceremonial sculptures.
