The welcome centers and service plazas usually consist of a large building or buildings with public restroom facilities, free brochures relating to nearby attractions, lodging, and dining, a free official state highway map updated at regular intervals, staffed desks for people to ask for assistance, picnic areas, nearby restaurants or onsite dining facilities, gas stations, and large parking lots.
In large cities like New Orleans or San Francisco, smaller cities like Astoria, Oregon or Vicksburg, Mississippi, as well as rural areas, visitor centers may be in a building of varied size with most of the above amenities included, i.e. restroom facilities, staffed desks for people to ask for assistance, nearby restaurants, free brochures relating to nearby attractions, lodging, and dining.
In addition, an urban or rural visitors center may have things of local, regional, or even national interest, such as rare and/or antiquated artifacts or small knickknacks (e.g. coins, stamps, or sports memorabilia).
Below is a list of welcome centers, visitors' centers and service plazas, as distinct from rest areas, in the United States, derived from a combination of state tourism websites and the Interstate Rest Areas website.
[3] The list includes the state agency responsible for the welcome centers and service plazas; the interstate, U.S. Route, state highway, or local street address that the welcome center or service plaza is located at; the city, the county or other political subdivision that the welcome center or service plaza's city is located in; and explanatory footnotes.