If you like mammoths, you're going to love this.
The two pits in Tultepec north of Mexico City are the first mammoth traps to be discovered, officials say.
Researchers from Mexico's National Institute of Anthropology and History said on Wednesday (local time) the pits were found during excavations on land that was to be used as a garbage dump. The human-made pits each measured about 1.7 metres (6 feet) deep and 25 metres wide, with 90-degree walls to prevent mammoths from climbing out.
At least 14 woolly mammoth skeletons have been uncovered in Mexico in traps built by humans about 15,000 years ago.
Big stash of bigger animals " This is the largest find of its kind ever made", the institute said in a statement (original text in Spanish).
The institute said hunters may have chased mammoths into the traps.
The skeletal remains were found in Tultepec, near the site where President Andres Manuel Lopez Obrador's Government is building a new airport for Mexico City.
Archaeologists at the prehistoric site believe they now have a better understanding of how hunter-gatherers would have tracked and killed mammoths in the Mexico basin. The holes housed hundreds of 15,000-year-old mammoth bones, leading scientists to deduce that they were purposefully ensnared in the quarry. When hunters finally caught him, they considered him "brave, fierce" and they "showed him respect" by laying out his bones in a ceremonial arrangement. "The herds grew, reproduced, died, were hunted", archaeologist Luis Cordoba told local media. Once the animal was separated, they would coax it into the human-built traps, kill it and then use it for food and other purposes. It's still unclear whether work on the dump will proceed.