Over 1,900 acres of Northern California property located between Folsom and El Dorado Hills is like “a layer cake of modern history,” according to Erin Hess, an archaeologist with the U.S. Army Corps of Engineers Sacramento District Regulatory Division. “This area includes everything from remnants of placer mining, hydraulic mining, dredge mining, dairy operations, roadside inns from the 1800s all the way up to Cold War-era missile research facilities,” said Hess.