Western section The western SH-15 begins at the Texas state line, connecting to Texas'
State Highway 15 between
Catesby and
Shattuck. It runs east for to
US-283, which it overlaps into Shattuck. In Shattuck, SH-15 splits off to the northeast, heading through
Gage and
Fargo, before ending in
Woodward.
Eastern section The eastern SH-15 picks up a US-64/412 south of Garber, and begins
concurrent with
State Highway 74 heading northbound. It splits from SH-74 to head through
Billings and has an interchange with
Interstate 35 at milemarker 203. It then has a five-mile (8.0 km) concurrency with
U.S. Highway 77. After leaving US-77, it passes through
Red Rock, and has a concurrency with
US-177, and splits off just north of the intersection with the
Cimarron Turnpike. It bridges
Sooner Lake and runs for 15 more miles (24 more km) before ending at
State Highway 18 north of Pawnee. ==History==