Mysterious 3,800-Year-Old Canaanite Arch and Stairway Unearthed in Israel

Archaeologists have made a stunning—yet thoroughly puzzling—discovery in northern Israel: a 3,800-year-old Canaanite arch and stairway, perfectly preserved underground.

Researchers don’t know the purpose of the structure, which was unearthed at the Tel Shimron archaeological site. They also don’t understand why it was sealed off not long after its construction.

But its preservation is “breathtaking, especially since the building material is unfired (!) mud brick—a material that only rarely survives a long time,” says excavation co-director Mario A.S. Martin, an archaeologist at the University of Innsbruck in Austria, in an email to Live Science’s Sascha Pare.

The brick corbelled arch hangs over a corridor inside of the structure found at Tel Shimron. Eyecon

Archaeologists haven’t historically paid much attention to Tel Shimron. Before the current dig began in 2017, the site had never been extensively excavated. Recently, the team stumbled upon a strange structure that appeared to be man-made.

“We kept digging down further, and it was preserved at a depth of one meter, then two meters, then three meters, then four meters,” excavation co-director Daniel Master, an archaeologist at Wheaton College, tells the Times of Israel’s Melanie Lidman. “This structure was totally intact, and suddenly we realized we were dealing with the foundation of a building or a superstructure that had been constructed at the top of the site.”

The team uncovered mud brick walls up to 13 feet (4 meters) thick, reports Ariel David of Haaretz. Strangely, no rooms were found within them. Instead, the inside was made up of a long corridor—which led to the mysterious arch. Beyond it, researchers found a staircase leading deeper underground.

Per Live Science, this arch is “corbelled,” meaning it’s made from layers of bricks built gradually inward. This design is sometimes called a “false arch,” while a “true arch” is made with specially shaped bricks that fit together. The Times of Israel reports that the newly discovered arch is the earliest example of corbelled architecture found in the country.

Soon after these structures were built, they were filled with sediment. “Why the passage went out of use so soon is a matter of speculation,” says Martin to Live Science. But the “fact is that it was done with full intent, and not because there was some imminent danger of collapse. For us archaeologists, the quick backfill is the most lucky piece of the whole story, since it is the only reason the feature is so incredibly well preserved almost 4,000 years later.”

These structures date to between 1800 and 1750 B.C.E., when a large Canaanite city stood at the site. The ancient city was an important trading hub mentioned in Egyptian writings at the time.

At first, the researchers thought the walls could have been built to protect the city from outside armies. Ultimately, however, the site’s layout didn’t support that theory.

Now, based on a few clues, they think the building may have been used for cultic purposes. The team found a Nahariya bowl, a type of seven-cupped pottery vessel used for ritual offerings, inside the corridor, per Haaretz. Additionally, thousands of bones belonging to animals that may have been sacrificed were found in a nearby structure.

While many questions remain, the discovery has been exciting for the researchers, who are used to slow, steady progress. “I’m going to spend the next few years convincing my students that this is not archaeology,” Master tells Haaretz. “You just don’t find huge, intact, vaulted passageways you can just walk through.”

In the future, the researchers want to learn more about the mysterious staircase. They plan to eventually “dig down from the other side to try to reach whatever this passage leads to from above,” Master adds. In the meantime, the site has been reburied to protect it from the elements.