Transportation System Overview

Highway System

  • Bridges: 20,034, including 8,443 state owned bridges, 11,591 locally owned bridges
  • Interstate miles: 1,201
  • 19 interstate rest areas
  • 16 interstate welcome centers
  • 9 truck weigh stations
  • State maintained highway miles: 14,462
  • Total highway miles: 96,187

Airport System

  • 71 General Aviation
  • 6 commercial

Rail System

  • 19 short line railroads on 817 miles of mainline rail
  • 6 class I rail lines on 2,138 route miles of rail

Transit System

28 transit systems serving all 95 counties: four large urban systems, eight small urban systems, 10 rural systems, one regional commuter transit system in Middle Tennessee, and local transit in five towns.


976 main channel miles of commercially navigable waterways and two ferries

Bicycle/Pedestrian System

  • 4,557 highway miles with 4-foot or greater shoulders to accommodate bicycles
  • 216 miles of state routes with designated bike lanes
  • 487 miles of greenways, sidewalks and trails
  • 172 miles of designated U.S. Bicycle Routes
  • 934 miles of sidewalks on state routes


On each gallon of gas, Tennessee motorists pay 27.4 cents state gas tax and 18.4 cents federal gas tax. Funds are dedicated for the Tennessee transportation system. For more information, visit the TDOT Finance Division web page or the TDOT Transportation Funding website.

Key Programs

TDOT SmartWay is the state's intelligent transportation system deployed in all four urban areas. The full complement includes a system of 551 cameras, 183 dynamic message signs and four transportation management centers to monitor traffic and assist in reducing congestion on urban interstates. Completed systems are located in Nashville, Knoxville and Memphis and in Chattanooga.

A rural TDOT SmartWay system is located in seven rural counties in east Tennessee and includes cameras to monitor the Rockwood Mountain section of I-40 in Roane County. 

The TDOT HELP program was launched in 1999 to help clear interstates of congestion by removing obstacles including vehicles from the travel lanes, thereby reducing traffic impacts. Since that time, thousands of motorists have been assisted and impacts to traffic have been reduced.

TDOT has motorist information programs, some of which use new communication tools such as TwitterFacebook and Tennessee 511, which aid motorists with highway information.

Several TDOT programs promote good driving behaviors through numerous public awareness efforts including Click It or Ticket.

Keeping our roads beautiful is important. These programs promote keeping our highways beautiful: Nobody Trashes Tennessee, Adopt-A-Highway, Keep Tennessee Beautiful and Tennessee Scenic Roadways.