The South Fork flows from the southern slopes of Thorofare Mountain.

The South Fork flows northeast from the Crazy Mountains.

Near its mouth the South Fork flows over a waterfall.

From the confluence the South Fork flows northwest.

Below the dam, the South Fork flows northwestward into the reservoir behind the concrete Arrowrock Dam, completed in 1915.

The South Fork originates in the northern Olympic Mountains and flows north and west to join the main stem Pysht.

The South Fork then flows north to a point where it turns sharply around a ridge and flows due south, then turns back north again.

The South Fork is the only unobstructed section and flows most of the year but not all the way to Cheyenne.

The South Fork flows westward in Grant County and passes the town of Milbank.

The South Fork flows northeast through a narrower wooded canyon, joining the Middle Fork lower down.