World Guide Covered Bridge (WGCB) numbers have been assigned by the National Society for the Preservation of Covered Bridges (NSPCB) are referenced for all listed bridges.  Assigned numbers are coded, such as NH-05-12 or VT-115-a.  The first two characters are the postal abbreviations for the state (formerly digits starting at 01 represented the state in alphabetical order).  The second two digits represents the county in alphabetical order starting at 01 for each state.  The third pair of characters represents the bridges place in the NSPCB tally of that county's bridges, starting at 01 for authentic truss type bridges or a letter for non authentic type bridges, an upper case letter for motor vehicle bridges, and a lower case letter for footbridges. Additionally, bridges that have a leading "(" before the last letter, are considered O.C.B.I. - "Of Covered Bridge Interest" - a Covered Bridge that is under 12' or is just on the ground and not over anything, i.e., 45-12-(b.

North Carolina general information:  North Carolina had a few hundred covered bridges gracing its roadways during the nineteenth and early twentieth centuries.  Randolph County alone had sixty covered bridges in the 1930s.  Currently, North Carolina has thirty six covered bridges, but only two are authentic and only one of these is Historic, Bunker Hill Bridge.  Of the thirty four non-authentic covered bridges, four are historic.  The thirty six covered bridges were constructed between circa 1860 and 2001.  These thirty six covered bridges were constructed between circa 1860 and 2001.   Twenty nine of North Carolina's covered bridges are located in the western part of the state.  All five of the historic covered bridges are closed to motor traffic, and three are privately owned.