11870b5d_oric_Significance_Rating__HSR___Description
[HSR] 6 [Examples] Riveted truss bridges with above-average historic integrity, later pin-connected truss bridges, and pin-connected truss bridges of any date with poor historic integrity. Post 1900 stone arch bridges. Larger concrete arch bridges with excellent historic integrity. Pre-1950 cantilever truss bridges. [Description] 
Again, standard and traditional designs fill the majority of this category, but the bridges in this category are clearly rare and have significant historic value. Bridges in this category clearly have historic value, yet are often facing demolition, and being assessed as non-historic.
HistoricBridges.org - Historic Significance Rating (HSR)
Description