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.

Rhode Island - General information.  There are records of only five authentic covered bridges that were built between 1820 and 1867 in the state of Rhode Island.  Rhode Island does, however, have the distinction of having the first covered interstate railroad bridge in the United States.  It was the India Point Covered Bridge, built across the Seekonk River for the Boston and Providence Railroad.  Of the five covered bridges, two were highway and three were railroad.  The last of the covered highway bridges was replaced by a wide concrete bridge in 1920.  Today, there are seven non authentic and one modern authentic covered bridges in Rhode Island.  Four of these are highway and four are footbridges.