It’s an old phobia: You've jut left home and are suddenly struck with the thought that you left something in the oven. But for a group of indigenous people 1,600 years ago, that fear was justified. Researchers at a new excavation site in Alberta uncovered a roasting pit with an untouched feast still inside.

The pit was excavated at Head-Smashed-In-Buffalo Jump, a UNESCO World Heritage site on the Blackfoot First Nations territory, reports Wallis Snowdon at CBC News. For 6,000 years at the site, plains hunters would stampede herds of bison over a cliff. They would then transport the animals to nearby camps where they could process the meat and feast.

The new discovery is a banquet that time forgot. “The unusual thing is someone prepared this meal and they didn't go back and open it up and eat it,” Bob Dawe, the lead archeologist on the project from Edmonton's Royal Alberta Museum, tells Snowdon. “It’s as unusual as if you were to put your turkey in the oven and never take it out for your turkey dinner.”

Dawe found the roasting pit in 1990, but didn’t excavate the site until recently, Andrew McCutcheon reports for the Calgary Herald. But it’s not as simple as taking a dish out of the oven. Roasting pits were constructed by digging a hole in the ground and lining it with rocks. Then willows were placed over the rocks and the meat was placed inside. The whole thing was covered in dirt and a fire lit on top, slow roasting the meat over night. The technique was used in Europe and many other cultures thousands of years ago and is still practiced in North America today at restaurants that cook authentic pit barbecue. Even the New England clam bake is a type of pit roasting.

It took over a month to remove and wrap the roasting pit, which is the size of a kitchen table, in plaster for transport to the Royal Alberta Museum. A crane finally lifted it out of the excavation site last week.

Broken arrowheads as well as the bones of a juvenile bison and a wolf-like animal were found near the roaster, giving some hint as to what was on the menu, but researchers will not know the exact contents until they remove the protective plaster casing and begin meticulously picking through the pit.

“Over the next few months, we’re going to very slowly excavate through it,” Dawe tells McCutcheon. “It’ll be a really slow process, because we’ll basically be excavating it with toothpicks and a small vacuum cleaner.”

After that, the roasting pit will be added to the museum’s permanent indigenous exhibit. But one question will likely never be answered: why didn’t anyone eat the meal? “There is no ready answer,” Dawe tells Snowdon. “It may have been a prairie fire or perhaps a blizzard, or maybe some other party of people interceded. We’re not really sure. We’ll never know.”