US 72 Alt. begins at an
intersection with
US 43/
US 72 in Muscle Shoals. Here, this road continues west as part of US 72. East of there, it intersects
SR 157 at an
at-grade intersection, where a
concurrency begins. A couple miles east of there, the roads split. SR 157 heads straight towards
Moulton. US 72 Alt. turns due east at the interchange, heading towards
Town Creek and
Decatur. US 72 Alt. enters Decatur after passing through
Trinity, carrying
SR 20. It serves as the northern terminus for The Beltline (
SR 67) and continues eastward towards the town center. After traveling by the
Old State Bank and the
Dancy Polk House in the downtown area, US 72 Alt. intersects
US 31. It continues over the
"Steamboat Bill" Hudson Memorial Bridge, after which it and SR 20 continue east towards
I-65 and
I-565, while US 31 continues north towards
Athens and
Calhoun Community College. The route is essentially unsigned east of US 31. After the interchange at I-65, US 72 Alt. becomes concurrent with I-565. The two routes run together for the entire length of I-565, passing through
Mooresville,
Madison, and
Huntsville passing through intersections such as the
University Drive and the elevated stretch. East of Downtown Huntsville, the routes ascend Chapman Mountain, where they intersect US 72, which serves as the eastern terminus for both I-565 and US 72A. ==Major intersections==