Incas used to be skillful architects, road builders as well as excellent astronomers. The Inca civilization reached the climax at the beginning of the 16 th century, when the Incas were at the head of a vast empire. Lured by that great wealth, the Spanish invaders, led by Francisco Pizarro, conquered the Incas and as of 1520 reigned over them for almost three centuries. It is thought that the last Inca ruler, Manko Inca, retreated in the mountains, in a place known today under the name of Machu Picchu . Little time after the conquest, the king of Spain appointed a viceroy in charge of enforcing of laws and religion, so that the natives got under the obligation to convert to Catholicism and to change their names for Spanish ones. Men, women and children were made to work on plantations and in mines. Lima , founded by Pizarro in 1535, became South America commercial, religious and cultural capital of that time. Currently, Peru is considered the archeological centre of South America, due to the numerous historical settlements, Machu Picchu , Cuzco , Pisac among many other.