State Route 400 (SR 400) is a

state highway A state highway, state road, or state route (and the equivalent provincial highway, provincial road, or provincial route) is usually a road that is either ''numbered'' or ''maintained'' by a sub-national state or province. A road numbered by a ...

Washington Washington commonly refers to: * Washington (state), United States * Washington, D.C., the capital of the United States ** A metonym for the federal government of the United States ** Washington metropolitan area, the metropolitan area centered on ...

and

Carter Carter(s), or Carter's, Tha Carter, or The Carter(s), may refer to: Geography United States * Carter, Arkansas, an unincorporated community * Carter, Mississippi, an unincorporated community * Carter, Montana, a census-designated place * Carter, ...

counties in the U.S. state of

Tennessee Tennessee ( , ), officially the State of Tennessee, is a landlocked state in the Southeastern region of the United States. Tennessee is the 36th-largest by area and the 15th-most populous of the 50 states. It is bordered by Kentucky to th ...

. It connects the cities of Johnson City,

Watauga Watauga can refer to: ;Places *Watauga, Kentucky * Watauga County, North Carolina * Watauga, South Dakota * Watauga, Tennessee * Watauga, Texas ;Bodies of Water * Watauga Lake in Tennessee * The Watauga River in North Carolina and Tennessee ;Shi ...

and

Elizabethton Elizabethton is a city in, and the county seat of Carter County, Tennessee, United States. Elizabethton is the historical site of the first independent American government (known as the Watauga Association, created in 1772) located west of both th ...

Route description

SR 400 begins as a pair of one way streets (Watauga and Unaka Avenues) at an intersection with SR 91 (which is also a pair of one way streets) in downtown Johnson City. It heads north to have an interchange with I-26/

US 23 } U.S. Route 23 or U.S. Highway 23 (US 23) is a major north–south U.S. Highway between Jacksonville, Florida, and Mackinaw City, Michigan. It is an original 1926 route which originally reached only as far south as Portsmouth, Ohio, and has since ...

/ US 19W (Exit 22) and continues northeast as a pair of one way streets. The northbound lanes then leave Watauga Avenue and turn northwest onto North Broadway Street and joins to the southbound lanes as Unaka Avenue and continues northeast to the city of

where SR 400 crosses over the

Watauga River The Watauga River () is a large stream of western North Carolina and East Tennessee. It is long with its headwaters in Linville Gap to the South Fork Holston River at Boone Lake. Course The Watauga River rises from a spring near the base ...

at the Johnson City/Watauga city boundary. SR 400 passes through downtown Watauga and turns more southeasterly and leaves the city of Watauga and continues southeast until it comes to an intersection with Old U.S. Route 19E. It then turns south and crosses over the Watauga River again and enters the city of

and continues south until its northern terminus at an intersection with

US 321 U.S. Route 321 (US 321) is a spur of U.S. Route 21. It runs for from Hardeeville, South Carolina to Lenoir City, Tennessee; with both serving as southern termini. It reaches its northernmost point at Elizabethton, Tennessee. Because o ...

/ SR 67 in Elizabethton.

Junction list

References

{{Reflist

400 __NOTOC__ Year 400 ( CD) was a leap year starting on Sunday (link will display the full calendar) of the Julian calendar. In the Roman Empire, it was known as the Year of the Consulship of Stilicho and Aurelianus (or, less frequently, year 11 ...

Transportation in Washington County, Tennessee Transportation in Carter County, Tennessee Johnson City, Tennessee Elizabethton, Tennessee