Geography

The Aztec Empire covered almost all of modern-day Mexico.

The Aztecs capital city was in the middle of a huge lake in central Mexico, Lake Texcoco. The capital city was Tenochtitlan.

The heart of the Aztec civilization lay in the Valley of Mexico, between Tenochtitlan and Teotihuacan.

Tenochtitlan

Since it was in the middle of a giant lake, the city was surrounded by water.  It also had canals throughout the city.

They built a causeway (land bridge) that connected the city to the main land of Mexico. On the main land they started to make chinampas.

Chinamaps were areas of soft land that floated on the water. The Aztecs planted crops on the chinampas, so the crops would continually get watered.

They did this because the climate in the area that the Aztecs lived it was very hot and humid. 

Aztec farmers creating Chinampas to grow crops.

In the present day Mexico the the city and lake of Tenochtitlan has been built over by Mexico City.

Check out the canals.  A sign of urban-planning.

Why is there smoke coming from the palace and temple?

A Spanish map of Tenochtitlan.  Not quite GPS, but good enough for a conquest.

Downtown Tenochtitlan.