River St. over the Clarks Fork of the Yellowstone R., Fromberg, Montana. County/parish: Carbon.
Added to the National Register of Historic Places January 28, 1993. NRIS 92001790.
1 contributing structure.
The Fromberg Concrete Arch Bridge, in Fromberg, Montana, was built in 1914. It was listed on the National Register of Historic Places in 1993. It carries River Street over the Clarks Fork Yellowstone River.
It is a three-span concrete deck arch bridge designed by Carbon County, Montana, surveyor C. A. Gibson and was "quite advanced for the time": it has "flattened parabolic arches with a rise to span ratio of 1 to 7." At its completion it was the largest concrete bridge in the state.
In 1993 it was the oldest multi-arch concrete bridge surviving in the state.
(read more...)National Park Service documentation: https://catalog.archives.gov/id/71974517