In which present-day country is Tenochtitlán located?

Tenochtitlán was an important ancient city that served as the capital of the Aztec Empire. It was located on an island in Lake Texcoco in present-day Mexico City. This historical significance is tied to the rise of the Aztecs as a major civilization in Mesoamerica, characterized by its impressive architecture, advanced agricultural practices, and complex societal structures. Today, the ruins of Tenochtitlán can still be explored in Mexico, particularly in the area around the Zócalo, which is the main square in Mexico City. The location of Tenochtitlán is therefore firmly established within the borders of modern-day Mexico, making it the correct answer.