State Route 155 (SR 155), mostly designated as Briley Parkway, is a major state highway that forms a beltway around Nashville, Tennessee, United States. The northern portion of the route is a freeway that forms a circular controlled-access bypass around downtown Nashville, along with I-440 to the south. The southern portion of the road is split into two major surface arterial roads called Thompson Lane to the south and White Bridge Road to the southwest. Both of these roads are connected by Woodmont Boulevard, which is not part of SR 155, but, combined, forms a complete loop. SR 155 has a total length , and transitions between being signed as a north–south and east–west road in multiple locations.

Briley Parkway, named in honor of former Nashville mayor Beverly Briley, serves as the primary means of access to the Grand Ole Opry House, Opry Mills, and the Opryland Hotel east of downtown Nashville. It crosses the Cumberland River twice, once near Madison, and again on the west side of Nashville, near John C. Tune Airport and the Riverbend Maximum Security Institution. Both of these crossings replaced ferries that had operated since the later 19th century. On the southeast portion of the loop, Briley Parkway passes Nashville International Airport. Along its length, the road provides access to multiple Interstate, U.S., and state highways.

SR 155 was first established around 1956 for Thompson Lane. Briley Parkway initially began as a project managed by the Nashville city government, with the first section opening in 1961. Most of the eastern segment was constructed in the 1960s, and some additional progress was made over the following decade. The city struggled to fund the project, and completion was further complicated by a number of factors including changing federal laws, public opposition, and failure to secure adequate federal and state funding sources. The state assumed control of the project in 1983, and the last section of Briley Parkway was completed in 1997. Between 1996 and 2007, much of SR 155 was widened in multiple phases. Several major interchanges were reconstructed and expanded between 2000 and 2011.

Route description The Briley Parkway and Thompson Lane sections of SR 155 are part of the National Highway System, a national network of roads identified as important to the United States' economy, defense, and mobility. The Briley Parkway portion is designated as a primary highway, and the Thompson Lane and White Bridge Road portions are designated secondary highways. On the freeway portion of SR 155, annual average daily traffic (AADT) volumes in 2024 ranged from 110,170 vehicles per day between Opry Mills Drive and Two Rivers Parkway to 27,171 vehicles between SR 12 (Ashland City Highway) and US 41A (Clarksville Pike). The lowest traffic volume on the surface-street portion of SR 155 was 21,631 vehicles per day on Thompson Lane between US 31 (Franklin Pike) and Iris Drive. Unlike the Interstates in Nashville, the controlled-access portion of SR 155 rarely experiences severe congestion. Unlike many ring roads which utilize inner–outer directional signage, SR 155 transitions between north–south and east–west signage three times as the cardinal directions of the route change. Driving the full length of SR 155 at the speed limit takes approximately one hour outside of rush hour.

Briley Parkway Briley Parkway consists of the northern loop of SR 155 from I-40 on the west side of Nashville to I-24 southeast of downtown Nashville, which makes up about two-thirds of the length of the highway. The entirety of Briley Parkway is a controlled access highway, except for the segment between I-24 and I-40, which is limited access. Exits are numbered counterclockwise, beginning at the southeast interchange with I-24 and extending to I-40 in West Nashville.

Briley Parkway begins as a four-lane freeway at a four-level stack interchange with I-40 in West Nashville where SR 155 continues to the south as White Bridge Road. Briley Parkway immediately curves northwest and then north, and briefly runs along the west bank of Richland Creek before crossing it. The first interchange is with Centennial Boulevard, which connects to Cockrill Bend Boulevard near John C. Tune Airport, Riverbend Maximum Security Institution, and an industrial area. The parkway immediately crosses a CSX rail spur that serves the industrial area and airport. SR 155 then curves northeast and crosses the Cumberland River before turning north and reaching an interchange with County Hospital Road near the University School of Nashville, the Debra K. Johnson Rehabilitation Center, and the old Tennessee State Prison. Continuing through further industrialized territory, the highway crosses the mainline railroad operated by Nashville and Eastern Railroad and reaches an interchange with SR 12 (Ashland City Highway) about later in the neighborhood of Northwest Nashville. Here, the parkway curves sharply to the northeast, running mostly west to east beyond this point on the northern edge of the urbanized parts of Nashville and Davidson County.

Passing through several deep artificial rock cuts flanked by tall limestone bluffs, the next interchange is with US 41A (Clarksville Pike) about later near the neighborhood of Haynes Estates. About later is an interchange with US 431 (Whites Creek Pike). About later, Briley Parkway reaches I-24 in a cloverleaf interchange. About beyond that is the next interchange, which is with Brick Church Pike. Beyond this point, Briley Parkway continues for another into the south end of the Madison neighborhood, and has a complicated stack interchange complex with US 31W/41 (Dickerson Pike) and I-65, then US 31E southbound (Ellington Parkway) less than later. At these interchanges, US 31W/41 (Dickerson Pike) and I-65 southbound are accessible together from both directions. From the westbound lanes, I-65 northbound and US 31E southbound (Ellington Parkway) are accessible together. From the eastbound lanes, I-65 northbound and US 31E southbound (Ellington Parkway) are concurrent with each other until the merge lanes end next to Goodpasture Christian School. Through this interchange complex, Briley Parkway is paralleled on both sides by local-express lanes that provide unobstructed access between I-65 and US 31E.

At this point, Briley Parkway widens from four to eight lanes and begins a brief concurrency with US 31E. The routes then pass under a CSX railroad, and US 31E splits off northbound as Gallatin Pike a short distance beyond in the northern part of the Inglewood neighborhood. The highway then crosses the Cumberland River again and curves sharply to the southeast. Here, the parkway enters the Music Valley entertainment district, and reaches a single-point urban interchange (SPUI) with McGavock Pike. This road is a connector road to the Gaylord Opryland Resort & Convention Center and the site of the Grand Ole Opry. Entering a short straightaway, Briley Parkway runs almost directly north-south at this point. Less than later, Briley Parkway has a trumpet interchange with a connector road to Opry Mills Mall, another major anchor of Music Valley. The next interchange, about later, is with Two Rivers Parkway. The parkway then shifts slightly to the west, before curving sharply to the east, and then to the west again, in somewhat of a c-shaped curve where it crosses the Nashville and Eastern Railroad again and briefly runs along the east bank of the Cumberland River. The freeway then reaches an interchange with US 70 (Lebanon Pike) in the Donelson neighborhood. The route shifts slightly again, maintaining its general north-south direction. Then, slightly over later is the next interchange, which is with Elm Hill Pike. The parkway then curves to the southwest, and reaches a three-level combination interchange with I-40 near the Nashville International Airport. Here, the route reduces to two lanes in each direction, and the freeway segment ends.

Continuing as a limited-access highway, Briley Parkway has at-grade signalized intersections with three major thoroughfares before reaching a trumpet interchange with Airways Boulevard, an exit to the former site of Nashville's Berry Field airport. The route continues for another mile, next to an aircraft manufacturing site adjacent to the airport, before reaching a SPUI with US 41/70S (Murfreesboro Road). Running northeast–southwest, Briley Parkway continues for another , crossing Mill Creek and another CSX line, before reaching a partial cloverleaf interchange with I-24. This partial cloverleaf interchange also includes access to a restricted connector road Averitt Express Drive, the entrance to an Averitt Express freight hub. The limited-access segment of Briley Parkway ends at this interchange. However, the Briley Parkway designation does not end until an intersection about later, where SR 155 becomes Thompson Lane.

White Bridge Road and Thompson Lane The segment of SR 155 designated as White Bridge Road begins at the interchange with I-40 in West Nashville, where the route continues north as controlled-access Briley Parkway. This entire section of SR 155 is a four-lane major arterial thoroughfare with many intersections with local roads. Beyond this point, the route immediately has an intersection with US 70 (Charlotte Avenue), and runs directly north-south before curving to the southeast over later near Nashville State Community College. The road then crosses Richland Creek and a CSX railroad on a single bridge and intersects US 70S (Harding Road) near Belle Meade. At this intersection, the route becomes two-lane Woodmont Boulevard, a city-maintained road, although many maps show this segment as being part of SR 155. About later, the road curves to the southeast, and begins running east-west nearly perfectly straight before reaching an intersection with US 431 (Hillsboro Pike).

About later, the route briefly enters the north end of the suburb of Oak Hill. Here, it widens back to four lanes and has an interchange with US 31 (Franklin Road), where the road becomes Thompson Lane, and SR 155 begins again. The route then crosses I-65 without an interchange and another CSX railroad, before intersecting with Powell Avenue near the city of Berry Hill, which contains signs directing drivers to I-65. Continuing east, Thompson Lane traverses through Woodlawn Memorial Park and then passes through a short and divided tunnel beneath the north end of a railyard that is part of the Nashville Terminal Subdivision operated by CSX. About later, the road intersects US 31A/41A (Nolensville Pike) in the Woodbine area. About later, the route reaches an intersection where Thompson Lane splits off to the north, and the route becomes Briley Parkway. The interchange with I-24 is less than beyond this point.

Honorary designations