Teotihuacán emerged as a major urban center in the Central Highlands of Mexico around 100 BCE, reaching its zenith between 150 CE and 650 CE, making it one of the largest and most influential cities of the pre-Columbian Americas.

The Pre-Hispanic City of Teotihuacan was designated a UNESCO World Heritage Site in 1987, recognized for its monumental structures and profound cultural significance as a testament to one of the most powerful Mesoamerican civilizations.

Geographically, Teotihuacán is situated in the Basin of Mexico, approximately 40 kilometers (25 miles) northeast of modern-day Mexico City, benefiting from fertile volcanic soils and access to water resources, although it faced challenges in water management.

The massive Pyramid of the Sun, standing over 65 meters (213 feet) tall, is the largest structure in Teotihuacán and the third-largest pyramid in the world, believed to have been completed around 200 CE and serving as a central ritual site.

Dominating the northern end of the Avenue of the Dead, the Pyramid of the Moon is the second-largest pyramid in the city, mirroring the sacred Cerro Gordo mountain behind it and serving as a site for sacrificial rituals and burials of high-status individuals.

The city's main thoroughfare, the Avenue of the Dead, stretches over 4 kilometers and is flanked by impressive ceremonial structures, culminating at the southern end in the vast Citadel enclosure, which houses the Temple of Quetzalcoatl.

Teotihuacán's art is renowned for its distinctive mural paintings, found in elite residential compounds, depicting deities, mythological creatures, ritual scenes, and geometric patterns, offering insights into their cosmology and daily life.

At its peak, Teotihuacán's population is estimated to have ranged from 100,000 to 200,000 inhabitants, making it one of the most populous cities in the ancient world and a melting pot of various Mesoamerican ethnic groups.

The city's economy was robust and diversified, relying heavily on agricultural production from chinampas, extensive obsidian tool manufacturing and trade, sophisticated ceramic production, and long-distance trade networks reaching across Mesoamerica.

Teotihuacán is celebrated for its highly advanced urban planning, characterized by a precise grid layout, sophisticated drainage systems, and monumental architecture aligned with astronomical principles, demonstrating a remarkable understanding of engineering and organization.

The mysterious collapse of Teotihuacán occurred around 650 CE, likely due to a combination of factors including internal social unrest, environmental degradation (deforestation, drought), and potential external pressures, leading to a gradual depopulation and abandonment of the urban core.

The Teotihuacano pantheon included prominent deities such as the Great Goddess of Teotihuacán, often associated with water and fertility, and the Feathered Serpent (Quetzalcoatl), whose cult influenced later Mesoamerican civilizations.

Despite its decline, Teotihuacán exerted profound influence on subsequent Mesoamerican cultures, including the Maya, Zapotec, and eventually the Aztec, who revered the site as a mythical "birthplace of the gods" and incorporated elements of its architectural and iconographic styles.

While no direct ancient festivals persist, the site hosts popular events like the "Equinox in Teotihuacán," where thousands gather to absorb "energy" on the spring equinox, and local communities preserve artisanal crafts and regional culinary traditions.

Today, Teotihuacán remains Mexico's most visited archaeological site, attracting millions of tourists annually who marvel at its monumental scale and architectural grandeur, contributing significantly to the regional economy through tourism and related services.