State Road 520 is a four-lane connector about 1,000 feet (300 m) in length.

U.S. 12 and U.S. 20 do not cross with each other — they parallel each other for another 22 miles (35 km) westbound and overlap in Gary; U.S. 20 is generally considered the faster of the two, while U.S. 12 is the scenic Dunes Highway.

U.S. 20 stays in Indiana and runs around Michigan City as a bypass to the south.

The road passes by a fire station before it meets US 12 at another 3-way intersection.

The entire route is in Town of Pines, Porter County.