Tunnelhill is a borough that is located in Cambria and Blair counties in Pennsylvania, United States.

According to the United States Census Bureau, the borough has a total area of 0.5 square miles (1.3 km2), all land.

Tunnelhill has the third-highest elevation among towns in Pennsylvania, at 2300 feet.

The racial makeup of the borough was 98.78% White, 0.24% Native American, 0.24% Asian, 0.24% Pacific Islander, and 0.49% from two or more races.

38.8% of all households were made up of individuals, and 21.9% had someone living alone who was 65 years of age or older.