State Route 91 (SR 91) is a 38.161-mile-long (61.414 km) state highway located entirely within Cullman County in the northern part of the U.S. state of Alabama. The southern terminus of the highway is at an intersection with SR 69 in Wilburn, a small unincorporated community in the southwestern part of the county that is also known as Bug Tussle. The northern terminus of the highway is at an intersection with U.S. Route 278 (US 278) in Holly Pond.

SR 91 is a two-lane highway that travels through rural areas of Cullman County. Although it is signed as a north–south highway, the first 8 miles (13 km) of the highway from its southern terminus actually travels in southeasterly direction. In Arkadelphia, the highway takes a virtual 90-degree turn to the left and assumes a northeasterly trajectory, which it maintains for the duration of its length.

SR 91 has an interchange with Interstate 65 (I-65) approximately 11 miles (18 km) southwest of Hanceville, and provides a connecting route for motorists heading to and from this town. Our Lady of the Angels Monastery, founded by Mother Angelica, is located near SR 91 between I-65 and Hanceville.

Much of the highway between Wilburn and I-65 is a narrow winding road through hilly rural terrain. In some places, the road is actually substandard for it to be a numbered state route. However, from I-65 north and east, the roadway is substantially better and contains less sharp turns and short sightlines.

The entire route is in Cullman County.

Location	mi	km	Destinations	Notes
Wilburn	0.000	0.000	SR 69	Southern terminus
Colony	14.538	23.397	I-65 – Huntsville, Birmingham	I-65 exit 291
Hanceville	25.179	40.522	US 31 (SR 3) – Cullman, Garden City
Holly Pond	38.161	61.414	US 278 (SR 74)	Northern terminus
1.000 mi = 1.609 km; 1.000 km = 0.621 mi

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