http://www.sciencemag.org/news/2019/07/ancient-people-may-have-used-pig-fat-build-stonehenge

The 30-ton megaliths that make up Stonehenge in Wiltshire, U.K., might have been moved using more than just elbow grease. Pig fat residue on nearby pottery could support the idea that builders greased sledges with lard or tallow to transport the stones, a new analysis suggests.

In the past, archaeologists have interpreted the high concentrations of pig fat on the pottery, found in the nearby prehistoric village of Durrington Walls, to mean the bucket-size ceramic vessels were used to cook feasts for hundreds of hungry Stonehenge builders. If prehistoric people used the vessels to cook pork, they would have had to chop the pigs into smaller pieces in order to fit in the pots. But the pig carcasses found at the site were whole and burned at the ends of the leg bones, which means they were probably roasted on a spit, researchers argue today in Antiquity. Instead, the team suggests the ceramic vessels may have been used to collect fat from the carcasses as they cooked, which was then stored as lard or tallow.