Started in 1910, this private collection consists of a wealth of objects - mostly from the Chorotega culture that flourished between AD 1250–1500. The curator is happy to lead you around and explain to you the purpose of the incense burners, various ceremonial objects, jaguar-headed metates and funereal urns. Also look out for the collection of wooden masks (c 1936) from the regional fiestas patronales (saints days).
Fun fact: the Chorotega didn't actually bury their dead in the funereal urns - those were the repositories for the bones of the already buried dead who would then be dug up three of four years after their demise, and re-interred in the urns.