The highway, completed in 1958 at a cost of $980,000 and designated in 1959, was originally built to provide access to the Mount Shasta Ski Bowl, which was destroyed by an avalanche in 1978. Today, the highway provides access to Mount Shasta for climbers, skiers, and anyone wanting access to the mountain.
In wintertime, the road is kept open only to the U.S.F.S outpost at the 6,000-foot (1,800 m) level.
County Route A12, known locally as the "99-97 cutoff", or more commonly, "the 97 cutoff", is a two-lane rural highway with a length of 17.9 miles (28.8 km). A12 begins in the west at its junction with Old 99 Highway, which was once US 99. Just a few dozen yards to the east, it intersects Interstate 5. Its eastern terminus is at US 97, 12 miles (19 km) north of Weed.
One mile east of the Interstate junction, it passes through the tiny village of Grenada, the only population center of any merit along the route. 7 miles (11 km) further east is the burg Mayten, which consists only of a convenience store, a church, and an elementary school.
The route is heavily used by travellers and truckers southbound on Interstate 5 who wish to use US 97 northbound en route to Klamath Falls and points north. This route saves over 13 miles (21 km) than if the alternative routing via I-5 to Weed, then north on US 97 was used. Hence, the local name "97 cutoff".
The western two-thirds of the route passes through agricultural areas, and is very reminiscent of two-lane farm roads in California's Central Valley. However, the eastern portion is very scenic, passing through an area with towering dark red crags and buttes to the north.
County Route A16 or Platina Road is a county route located in Shasta County connecting SR 36 to SR 273 in Redding. Known locally as Ditch Grade Road ;the final 6.5-mile (10.5 km) section before the junction with SR 36 closely follows the contour of hillside as this route was previously used to bring water to the mine at Platina. There is a rock formation some 6.5 miles (10.5 km) from SR 36 known as Old Man rock or The Lincoln Memorial .
A28 begins in Grenada, connecting Grenada with Hornbrook via Montague. It is a flat, level route, and for this reason, was the original preferred routing for both US 99 and Interstate 5 through the area. In both instances, the routing was changed because of intense lobbying by officials in Yreka, who decried the fact that the major highway through the county would bypass the county seat. Thus, both highways ended up being built over far more rigorous terrain at a huge cost increase.
A28 serves the aforementioned three towns, as well as numerous homes and ranches along the way.