One of the strangest mysteries in archaeology was discovered in the Diquis Delta of Costa Rica. Since the 1930s, hundreds of stone balls have been documented, ranging in size from a few centimetres to over two meters in diameter. Some weigh 16 tons. Almost all of them are made of granodiorite, a hard, igneous stone. These objects are monolithic sculptures made by human hands.
The spheres number over 300. The large ones weigh many tons. Today, they decorate official buildings such as the Asamblea Legislativa, hospitals and schools. You can find them in museums. You can also find them as ubiquitous status symbols adorning the homes and gardens of the rich and powerful.
The stones may have come from the bed of the Térraba River, to where they were transported by natural processes from sources of parent material in the Talamanca mountains. Unfinished spheres were never found. Like the monoliths of the Old World, the Costa Rican quarry was more than 50 miles away from the final resting place of these mysteries.