Louisiana Highway 159 (LA 159) runs 31.76 miles (51.11 km) in a north–south direction from a junction with I-20 and US 371 in Minden to the Arkansas state line north of Shongaloo, Webster Parish.

It makes twists and turns through northern Bossier Parish before reaching its eastern terminus at a T-intersection with LA 157 at a point known as Midway.

[13] The route begins at an intersection with Gorton Road, south of Lake Bistineau State Park.

It begins to parallel the Kansas City Southern railroad tracks and after 1.4 miles (2.3 km), it enters Webster Parish.

Louisiana Highway 166 (LA 166) ran from the Bossier-Webster parish line southwest of Doyline to a point near Lake Bistineau.

[15] The route heads northeast from LA 1 in the village of Rodessa, immediately crossing the Kansas City Southern railroad tracks before turning east at Pitts Road.

It then begins a 0.5 miles (0.80 km) concurrency with US 79/US 80 through Greenwood before splitting off to the north just south of an interchange with I-20 at Exit 3.

After this interchange, LA 169 then begins a generally northward course for 16.4 miles (26.4 km) before entering the town of Mooringsport.

It intersects LA 538, immediately crossing the Kansas City Southern railroad tracks before continuing east out of Mooringsport.

[17] The route heads east from the Texas state line until curving to the southeast upon entering Vivian, becoming Tennessee Avenue.

[20] The route heads east from LA 191, which runs along the Toledo Bend Reservoir, and intersects US 171 in Converse.

[25][26][27] In Mansfield, LA 175 intersects US 84 and turns west to follow that highway briefly before resuming a northern course through points such as Bayou Pierre and Holly.

[25][26][28] The highway proceeds northeast through Frierson into Caddo Parish, where it reaches its terminus at LA 1 southeast of Shreveport.

[30] It parallels US 167, the city's primary north–south highway, from a point near the downtown area to the northern limit at Carencro.

The route begins at US 90 and US 167, which run concurrently along Northwest and Northeast Evangeline Thruway, a couplet of one-way streets.

LA 176 initially heads northeast along Jefferson Boulevard as an undivided four-lane highway.

After three blocks, it turns north onto Moss Street and passes along the west side of Lafayette's City Park, crossing the Louisiana and Delta Railroad (LDRR) tracks immediately afterward.

1.2 miles (1.9 km) later, LA 176 intersects West/East Alexander Street and widens to accommodate a center turning lane.

[40] The route is a short connector between US 71 and US 165 at the point where the two highways diverge in Pineville, just north of Alexandria.

[22][40][41] As its local name indicates, the route was once a small part of the historic Jefferson Highway auto trail which extended from New Orleans to Winnipeg, Manitoba, Canada in the late 1910s and 1920s.

[41][42] The deleted portion, though no longer state-maintained, retains destination signage directing traffic from US 165 Business toward US 71 and US 165, heading toward Shreveport and Monroe, respectively.

[45] Louisiana Highway 184 (LA 184) runs 3.38 miles (5.44 km) in a north–south direction along Chaffee Road east of Leesville, Vernon Parish.

State maintenance ends a short distance later at an intersection with Pendleton Drive, which leads to a residential area within the base.

[50] It connected Barksdale Air Force Base to LA 72, which leads to several main highways in the area.

Destination signage on LA 72 also directs motorists onto Northgate Road to reach the Eighth Air Force Museum located within the base.

LA 185 headed southeast as an undivided four-lane highway and gained a center turning lane as it entered a residential neighborhood.

[51][53] After rehabilitation of the roadway in 2013, La DOTD turned the route over to the government of Bossier City as part of its Road Transfer Program.