Inventions of the Inca civilization

The Inca Empire was a major civilization located in South America, starting in Peru. They appeared around the 12th century in a village called Paqari-tampu. The empire stretched from Chile up to Southwestern Columbia and was as wide as Bolivia. The Inca's capital was Cuzco, founded in 1438. They retained their land until the Spanish arrived in South America in 1532. During this time the Inca Empire was in a state of civil war due to the death of their first and greatest emperor Pachacuti. He was the main cause for its expansion, wealth,  harmony, and religious pantheon. The Inca Empire's rise to power and downfall was caused by its geological location, its emperors, and its expansion. There were around 12 million people and they had 30 different languages in the empire. 65% of their people died of smallpox while the two kids of the king fought for the crown starting a civil war.