There could be a garden just beneath the waters. Kurt Bauschardt/CC BY-SA 2.0

It’s not exactly Atlantis, but archaeologists have discovered what might be the oldest example of a garden ever found in the Pacific Northwest.

According to Science, archaeologists discovered the garden just east of Vancouver, hidden beneath the waters of a natural wetland, at a site labelled, DhRp-52. The researchers found 40 square meters of tightly interlinked stones that created a sort of unbroken pavement. Also found at the site were various crude digging tools and around 4,000 wapato tubers, an edible plant not unlike a potato which is thought to have been the main crop of the garden.

The garden is thought to have been created by the Katzie, a First Nations people in British Columbia, and it’s been dated to around 3,800 years old, making it possibly the oldest surviving garden structure in the region. The people that built the garden likely lived on a nearby dry spot of land while using the shallow wetland to grow their swamp potatoes, according to Science.

The rice-paddy-like site is also an important window into exactly how agriculture developed in the area, where the actual structure still exists rather than simply having documentary evidence. Still, the tubers don’t look very appetizing.