The ancient city of Teotihuacán, located in what is now Mexico, was once one of the largest and most powerful cities in the pre-Columbian Americas. The city was home to an estimated 100,000 people and covered an area of over 8 square miles. Teotihuacán was a major cultural, political, and economic center, and its influence can be seen in many other Mesoamerican cities.

The city was founded around 100 BCE and reached its peak between 100 and 750 CE. Teotihuacán was abandoned around 750 CE, and its ruins were largely forgotten until the 19th century.

The city's urban design was one of its most distinctive features. The city was laid out on a grid plan, with wide boulevards and plazas. The most important buildings in the city were located along the main avenue, which ran north-south. The avenue was flanked by two large pyramids, the Pyramid of the Sun and the Pyramid of the Moon.

The Pyramid of the Sun is the largest pyramid in the Americas. It is estimated to have been built between 100 and 200 CE. The pyramid is made of adobe bricks and is over 213 feet tall. The Pyramid of the Moon is the second largest pyramid in Teotihuacán. It is estimated to have been built between 200 and 400 CE. The pyramid is made of adobe bricks and is over 155 feet tall.

Teotihuacán was also home to many other impressive buildings. The city had several temples, palaces, workshops, and residential complexes. The city was also surrounded by a wall, which was over 11 miles long.

Teotihuacán's urban design was a major influence on other Mesoamerican cities. The city's grid plan and large pyramids can be seen in many other cities, such as Tikal and Copán. Teotihuacán's urban design was also a major influence on the architecture of the Aztecs, who built the city of Tenochtitlán in the 14th century.

Teotihuacán was abandoned around 750 CE. The reasons for the city's abandonment are still unknown. Some scholars believe that the city was abandoned due to a drought, while others believe that the city was abandoned due to a war or an invasion.

The ruins of Teotihuacán were largely forgotten until the 19th century. In the 1800s, the Mexican government began to excavate the ruins of the city. The excavations revealed the city's impressive architecture and urban design. Teotihuacán is now a popular tourist destination, and it is considered to be one of the most important archaeological sites in the world.