Tourism in Peru tourism forms the largest sector of the tourism industry in Peru. Pre-Columbian civilizations – most notably the Inca Empire, Chavín, Moche, and Nasca – left a large archeological and cultural impact on the nation. The ruins of Machu Picchu are the most internationally recognized of all the ruins of Peru and therefore receive the most tourists. The other popular ruins are those of Chan Chan, Sipán, Kuelap, Nazca Lines, Ollantaytambo, Caral, Sacsayhuamán, and Sillustani. Tourists also visit the Spanish colonial architecture in many cities in Peru. Some of the most outstanding examples of Spanish colonial architecture are in the cities
Metallurgy in pre-Columbian America chemically altering it by alloying it. To date "no one has found evidence that points to the use of melting, smelting and casting in prehistoric eastern North America." In South America the case is quite different. Indigenous South Americans had full metallurgy with smelting and various metals being purposely alloyed. Metallurgy in Mesoamerica and Western Mexico may have developed following contact with South America through Ecuadorian marine traders. South American metal working seems to have developed in the Andean region of modern Peru, Bolivia, Ecuador, Chile, and Argentina with gold and copper being hammered and shaped into intricate objects, particularly