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
Pre-Columbian era Oceania of several cultivated plant species native to South America, such as the bottle gourd ("Lagenaria siceraria") or sweet potato ("Ipomoea batatas"). Direct archaeological evidence for such pre-Columbian contacts and transport have not emerged. Similarities noted in names of edible roots in Maori and Ecuadorian languages ("kumari") and Melanesian and Chilean ("gaddu") have been inconclusive. A 2007 paper published in "PNAS" put forward DNA and archaeological evidence that domesticated chickens had been introduced into South America via Polynesia by late pre-Columbian times. These findings were challenged by a later study published in the same journal, that cast doubt on the