The Incas were master builders. They created a huge network of roads that crisscrossed the empire and tied its farthest reaches to the capital at Cuzco. Working mostly with stone, the Incas constructed entire cities, filled with public buildings of monumental size. Furthermore, to give themselves more farmland in their mountainous homeland, they carved agricultural terraces out of the sides of mountains.

The engineers and architects who designed these projects were part of the Incan aristocracy and were extremely skilled at their jobs. Indeed, many of the monumental projects of the Incas have survived to the present. Civil engineer Kenneth R. Wright and archaeologist Alfredo Valencia Zegarra point out that "the well-preserved remains of [the Incan city of] Machu Picchu show that they had an advanced understanding of such principles as urban planning, ... drainage, and durable construction methods."

The Roads

Planning and constructing roads was one...