An ancient village has been discovered in Arizona’s Petrified Forest National Park by archaeologists, reports ABC News’ Good Morning America. The 1,300 year old dwellings are similar to another concentrated area of slab-lined pit-houses unearthed last year by researchers exploring new sections of the park, which was designated a national park by Congress’s Petrified Forest National Park Expansion Act of 2004.

Both sites, which are located in sand dunes less than a kilometer apart from each other, are thought to have been inhabited by a semi-nomadic community. Based on analysis of pottery samples at the newly discovered village, the community is thought to date to between 200 A.D. and 700 A.D.

According to Bill Reitze, the park’s archaeologist, such sunken homes are unique to the Southern Colorado Plateau, and while common throughout the park, are rarely found grouped together in such large numbers. In its heyday, the Petrified Forest was home to both the Navajo and Apache people, who lived in adjacent counties.

“Because the park is doubling in size, we are finding something every day–certainly not like these sites, but we are finding things every day,” he told ABC News.

Most of the artifacts found are stone tools such as spear points and knives. The inhabitants also produced objects made of petrified wood, shells, and ceramics, like a white soapstone or siltstone carved pendant that Reitze calls “really neat.” As more artifacts turn up, archaeologists will employ radiocarbon dating on their findings.

“There are not a lot of national parks that have the opportunity to get bigger like this to protect sites and produce future research,” Reitze added. “A lot of archaeology happens in response to development. What makes this unique is new sites are discovered, research [is] being done and all these sites are being protected, all at once.”