[2] Colerain Township is located in central Bedford County in the Appalachian valley known as Friends Cove.

The Silurian Tuscarora Formation, a hard sandstone, outcrops at the crests of the ridges and is stratigraphically higher and thus younger than the rest of the bedrock in the valley.

The low knobs or "benches" on the northwest side of Tussey Mountain and the southeast side of Evitts Mountain are formed by the Ordovician Bald Eagle Formation, another sandstone, that is stratigraphically below the Tuscarora.

[4] Portions of the Pennsylvania State Game Lands Number 97 is located along the southeastern border of the township.

The racial makeup of the township was 99.04% White, 0.26% African American, 0.17% Asian, and 0.52% from two or more races.