The geological stratum on which the city rests is the sedimentary formation Berea sandstone, a geological formation named after the city which extends across Ohio, eastern Pennsylvania, and northern Kentucky. This comprises a sandstone laid down during the early Mississippian. In the 19th and early 20th century, this formation was extensively quarried, with the quarries eventually displacing the original main street of the town, as well as the original location of Baldwin University, which sold its five-acre campus to the quarries for $100,000 in 1888, moving to a new location to the north.