Petrospheres or stone balls are pre-Columbian carvings found only in Costa Rica (One has been found just over the border in Panamá). They are almost perfectly spherical, and many are finely polished some are a more than 2 meters (six feet) in diameter. The largest found to date weighs over 15 tons. They were carved without the aid of metal tools, and some were transported hundreds of kilometers despite the Indians having no wheel nor beasts of burden. This is a short documentary in two parts each about 8 minutes long.