At the height of the Empire in the 16th century, the Inca civilization stretched across the western region of South America between Ecuador and Chile, encompassing land in what is now Peru, Chile, Bolivia and Argentina. This area is mountainous, hot and dry, but nevertheless, the Inca were able to produce food for their large population through adaptive farming practices and the building of advanced irrigation systems.
One of the main adaptive farming practices used by the Inca was terrace farming. Through this practice, the Inca people built steps along the sides of mountains, essentially creating flat land where there originally was none. Instead of flowing down the slope of the hill, water would pool on the flat surfaces of the steps, providing the crops with more moisture. Through the use of terrace farming, the Inca people were able to grow such crops as potatoes, peanuts, cotton, quinoa and tomatoes.
The Inca people also found ways to make the barren soil in South America more fertile and suitable for farming. According to All Empires, they used bat guano and bird excrement as fertilizers. They also built aqueducts to carry water to dryer lands. They even constructed an immense system of roads, which allowed them to travel across their vast empire more efficiently.