A herd of Pronghorns bask in the sunset June 19 at the Plains Conservation Center. This Saturday, Colorado breweries, local food trucks and musicians will join the wildlife during the 10th annual Hops for Habitat fundraiser. The money earned will go towards the center’s main expansion project, known as the West Bijou, which will implement restorative grazing areas for bison herds in the area. (Marla R. Keown/Aurora Sentinel)

AURORA | An eastern parcel of land managed by local nonprofit organization, Plains Conservation Center, was recently named the country’s 599th national natural landmark, the National Park Service announced in a press release Nov. 17.

Sally Jewell, U.S. Secretary of the Interior, on Nov. 15 officially designated the PCC’s West Bijou Site — a nearly 8,000-acre swath of grassland located south of Strasburg — the country’s newest national natural landmark.

The PCC’s main site is located along Aurora’s E-470 corridor off East Hampden Avenue.

The National Park Service pointed to a rich fossil layer located throughout the sweeping West Bijou parcel as the reason for the recent designation.

“The information contained in that thin sediment band illustrates the key feature of national natural landmarks as significant natural areas recognized for their irreplaceable features,” Jonathan B. Jarvis, national park service director, said in a statement. “They teach us extraordinary lessons about the world around us. The National Park Service partners with landmark owners in support of their voluntary conservation of these important areas, another important feature of the program.”

A 1.18-inch layer of sediments runs across much of the West Bijou Site, according to the NPS. The band marks the extinction of the dinosaurs, a period of time known as the Cretaceous-Paleogene boundary, and the beginning of the Cenozoic Era.

The National Natural Landmarks Program has been run by the National Park Service since 1962.

The PCC announced plans in early September to shift control of its 1,100-acre site in Aurora from its eponymous nonprofit organization to the city’s Parks, Recreation and Open Space Department and Denver Botanic Gardens. The Center began running educational programs through the Botanic Gardens late last year, and the city’s PROS department has helped to maintain the sites since 1997.

“We are thrilled that West Bijou, meaning Jewel, is the 599th site to be designated as a National Natural Landmark,” Becca Rose, interim CEO at the Plains Conservation Center, wrote in an email. “We believe this designation recognizes the important contributions West Bijou provides to the local community and supports the ongoing mission and vision of Plains Conservation Center.”

Correction: An earlier version of this story inaccurately depicted the Plains Conservation Center’s management plans. The PCC is only working on restructuring control of the Aurora site. Management of the Strasburg site will not change.