The Inca faced many problems based upon their geography and their political structure. Living in the mountains isn't easy for a number of reasons. There is much less to eat than in most flat-land places. The Inca had to come up with new strategies for growing food, most notably cutting terraces into the side of hills to create flat space for growing corn. They built a huge series of roads, perhaps more roads than any other place in the world at the time, to connect distant places. Finally, they used a political system where the children of tribal leaders far away from the empire's center would come to Cuzco, the capital, to be integrated into Incan society.