Terrace farming

Terrace farming (also called step farming) is a method of farming that consists of different "steps" or terraces that were developed in various places around the world. The Rice Terraces of the Philippine Cordilleras (hills and mountains) is a World Heritage Site. It dates back two thousand years.
This method of farming uses "steps" that are built into the side of a mountain or hill. On each level, various crops are planted. When it rains, instead of washing away all of the nutrients in the soil, the nutrients are carried down to the next level. These steps prevent water from washing away the soil and plants. This system also allowed them to build aqueducts, which carried water to each level.
The idea was also independently developed by the Inca people. The Incas built their aqueduct system so well that it is still used today.