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.

Connecticut - General information. At one time Connecticut had over sixty highway and railroad bridges covered bridges. Most of these were in the western part of the state. Records indicate only a dozen existed east of the Connecticut River. Most of the covered railroad bridges served predecessors of the New Haven Railroad. The first covered highway bridge in Connecticut was built as early as 1818. It was the massive 974 foot long Hartford Toll Bridge by Ithiel Town and built by Town and Isaac Damon of Northampton, Massachusetts. The original cost to build the bridge was $40,000. Tolls were collected for 70 years to provide a return on the initial investment. In 1889, the five towns that benefited most from the use of the bridge purchased it and removed the toll. It was destroyed by fire on the night of May 17, 1895. Flames started in the East Hartford end of the bridge and spread through the entire structure within ten minutes while a crowd of approximately twenty thousand townspeople lined the banks of the river looked on. Today, only three historic covered bridges still exit in Connecticut. All the covered railroad bridges have disappeared. In addition, to the three historic bridges still standing, there are two twentieth century covered bridges, and a contemporary bridge.