One of the reasons is its over 700-year old aqueduct, still functional today, as is its calzada, a stone walkway used as a transit route and part of the drainage system. The calzada leads towards a ceremonial center, where it is possible to observe several mounds which at one time served as supports for the famous conical roofed straw and reed structures of South American influence. Stone was commonly used in Guayabo to build a system of sidewalks and walls that helped prevent erosion and landslides. There are also stone tombs decorated with pebbles, flagstones and engravings or petroglyphs.
Guayabo was constructed between 300 B.C. and 1.400 A.D. and was populated by indigenous groups of the Intermediate Cultural Area, which extended from Alajuela, in Costa Rica, all the way to Colombia, Venezuela and part of Ecuador. Despite the fact that Guayabo was no longer populated when the Spaniards arrived and the causes of its depopulation are still a mystery, the site was for centuries undoubtedly a highly developed cultural and political-religious center, whose importance was heightened precisely because of its rich resources and the presence of the Turrialba Volcano.
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