High Quality Content by WIKIPEDIA articles! Guayabo de Turrialba is an archeological site located in Turrialba, Costa Rica. The site is of great archeological and cultural importance even though only a very small portion of the city has been uncovered and studied. The monument covers 540 acres (218 ha) and is located on the forested southern slope of Turrialba Volcano. The settlement was occupied between 1000 BC and 1400 AD after which it was mysteriously abandoned. The reason is still unclear and the Spanish Conquistadors and settlers did not leave any record as to whether they found the ruins.