Costa Rica’s only remaining ancient archaeological that is accessible to visitors, the Guayabo National Monument is situated a 20 kilometre drive from Turrialba. A tour of the partially-excavated site leads you past some of the remaining tombs, carvings and aqueduct remnants of this ancient town, thought to have been inhabited from approximately 300 BC to around 1400 AD. Little is known about why the inhabitants suddenly abandoned the area, but exploring the forest surroundings here can be almost as enjoyable as the ruins themselves, with monkeys and sloth sometimes seen, as well as a variety of birds.