The pyramids of the Sun and the Moon
Teotihuacán was one of the largest cities in the world around the first centuries AD, long before the Aztecs arrived and gave it the name meaning roughly 'place where the gods were created'. The Avenue of the Dead runs for over two kilometres past the massive Pyramid of the Sun and ends at the Pyramid of the Moon. The Temple of the Feathered Serpent still has carved heads of the god Quetzalcóatl. Arrive early to beat the heat and crowds, or see it from a hot-air balloon at sunrise. It's an easy day trip from Mexico City.