Monumento Nacional GuayaboThe major archaeological site in Costa Rica is the Monumento Nacional Guayabo, which is about 85 kms east of the capital of San José. Guayabo is currently under investigation and is thought to have been inhabited from about 500 B.C. to 1400 A.D. Streets, aqueducts and causeways may have been seen, though most of the buildings have collapsed and have not been yet restored. Gold and stone artifacts have been discovered there. Archaeologists believe Guayabo was an important religious and cultural center, although minor compared to Aztec Inca or Maya sites.