Achievements of the Classical Empires Classical Empire construction of the Great Wall
the great city of Machu Picchu
the great temple at Palenque, built by Pacal
invention of the sundial and seismograph
accurate calendars and astronomical observatories
elaborate roads and bridges
domestication of animals
invention of Hindu-Arabic numerals
the great city of Tenochtitlan
out of these Han dynasty of China, the Gupta Empire of India, and the Aztec, Inca, and Maya Empires