Castell Henllys is the site of an Iron Age village in the Welsh Pembrokeshire Coast National Park. It was once home to a wealthy family that included a community of up to 100 people who worked together to produce food and materials 2,000 years ago. The site includes four reconstructed roundhouses, which are circular structures with conical roofs made of wood and straw. Archaeologists and researchers rebuilt these structures using the same materials villagers would have used during the Iron Age.
     After standing for nearly 30 years each and being visited by countless tourists and about 6,000 school children per year, the sites of the roundhouses provided a unique opportunity for researchers. What began as an experiment to understand how building materials decay and degrade over time turned into something else when the researchers uncovered a wealth of plastic - 2,000 plastic items to be exact.
     Although the historic site is well maintained and cleaned, small plastic remnants of activity by visitors - children routinely eating lunches in one of the structures - were able to hide beneath benches in dark corners of the roundhouses. Among the plastic fragments were utensils, bottle caps, straws, straw wrappers, plastic bags, plastic food wrap, candy wrappers and even apple stickers.
     "The amount of plastic litter was a surprise," said Professor Harold Mytum, lead researcher and professor of archaeology at the University of Liverpool. "The plastic creates an archaeological signature of our time (the Anthropocene), but one which is environmentally damaging," Mytum said.
     The team said the discoveries would help uncover how and where plastic waste accumulates, to reduce the amount incorporated in the ground. They are also working with Pembrokeshire Coast National Park to help educate the public and raise awareness over environmental concerns that might be raised by something so simple as a school packed lunch. But Mytum also said he hoped the Plastic Age did not last millennia, like the Iron Age. "With many initiatives now pushing to switch from disposable plastic and plasticised items, this may be a narrow, but archaeologically distinctive chronological horizon," he added.

Edited from University of Liverpool, CNN World, CNN WorldBBC News (7 January 2021)