Major junctions include LA 1 in Plaquemine, the main route connecting the communities situated along the west bank of the Mississippi River.

LA 75 was designated in the 1955 Louisiana Highway renumbering and initially followed a more distinct north–south route through Iberville Parish.

LA 75 travels northward as an undivided two-lane highway along the east bank of the Lower Grand River.

[2][3][4] Upon entering the city of Plaquemine, LA 75 widens to an undivided four-lane highway with a center turning lane.

The highway passes through Sunshine, a small community now within the city limits, and bends southward with the river levee.

The highway turns eastward, following a sharp bend in the river, and ends soon afterward at a junction with LA 22 in Darrow.

[2] The portion of LA 75 extending from the Plaquemine Ferry to Darrow is a small part of the multi-state National Scenic Byway known as the Great River Road.

This alignment was bypassed by an extension of former LA 992-2, and the Mississippi River ferry was moved downstream from its previous location at Court Street accordingly.

[15] La DOTD is currently engaged in a program that aims to transfer about 5,000 miles (8,000 km) of state-owned roadways to local governments over the next several years.

[17][18] Louisiana Highway 75 Spur (LA 75 Spur) runs 0.18 miles (0.29 km) in a southwest to northeast direction, consisting largely of a swing bridge across the Lower Grand River (a link in the Gulf Intracoastal Waterway) in the small Iberville Parish community of Bayou Sorrel.