| KY 307 at South Fulton|| 91.39 km|
| US 45/US 45W at Three Way|
Martin, Milan, South Fulton, Greenfield, Medina, Three Way, Bradford
Madison County, Tennessee
State Route 43 is a south to north highway in Tennessee that is 56.79 miles (91.39 km) long. It begins in Madison County and ends in Obion County. State Route 43 is little-known by the general public by this designation as it is overlain by U.S. Route 45E for most of its length; the "43" designation is seen largely on mileposts. Two short sections of this route at Martin and South Fulton is fully signed.
Tennessee State Route 43 Wikipedia
Most of SR 43 is a four-lane divided highway, which either overlies or bypasses its original route. It begins at Three Way as a divided four-lane, overlain by US 45E, bypasses Medina, and goes through Milan as an undivided four-lane. SR 43 from its southern terminus to Milan is designated as a Strategic Highway Network connector route servicing the Milan Arsenal. North of Milan, it becomes divided again and bypasses Bradford, passes through Greenfield undivided, divides again and bypasses Sharon.
At Martin, SR 43 breaks free from US 45E as a signed highway and bypasses Martin to the west. This road is the original US 45E around Martin, TN. It is not limited access, and because of its location, it could not easily be converted into a four-lane limited access highway in the 1990s. As a result, a new divided, limited-access four-lane US 45E was constructed around the east side of Martin where more land was available, and the original SR 43 designation was revealed on signposts.
North of Martin, SR 43 rejoins US 45E and continues as an undivided four-lane highway to South Fulton, where it breaks free again and follows the original US 45E Business Route through town to the Kentucky state line while 45E bypasses to the west.
State Route 43 traverses the counties shown in the table below.