First description is from the French Explorers Pere Jacques Marquette and Louis Joliet traveling the Mississippi River in 1673. Jean Jean-Bapiste Louise Franquelin drew the following from their description.
The Plains of Jars. Thousands of giant stone jars are scattered around the Xieng Khouang plain in Laos. Excavation by Lao and Japanese archaeologists has supported the conclusion that these were funeral megaliths, with the discovery of human remains, burial goods and ceramics found in association with the stone jars. The Plain of Jars is dated to the Iron Age (500 BCE to 500 CE). Image: Anne Murray.
Ancient Egyptian statues were supposedly hacked out with copper chisels and stone pounders. And yet many of these statues have been found to be prefectly symmetrical. We would struggle to acheieve this today, so how did these ancient stone worked achieve such high precision?~~~~Did you look at the picture before you wrote that?