Mystery Bridge except for the fact that the bridge did exist along the former Bonnie Doon line: http://thebridgehunter.areavoices.com/2016/08/15/mystery-bri...
The north approach of the bridge collapsed in 1968. The bridge was closed to traffic but the farmers still use ituntil the 1980's.
Bridge in the 1930's
http://ortho.gis.iastate.edu/client_pls.cgi?zoom=1&x0=240895...
Bridge in the 1960's
http://ortho.gis.iastate.edu/client_pls.cgi?action=south&zoo...
Bridge in the 1980's
http://ortho.gis.iastate.edu/client_pls.cgi?zoom=1&x0=240941...
conclusion: Bridge was converted to a road bridge at some point, served as a road until the collapse between 1980 and 1994....
This bridge was a road bridge on the original hiway 75 or KT trail from Rock Rapids to Doon. However it was never a railroad bridge for the Bonnie Doon railroad as speculated in the article, Old plat maps clearly show the railroad and roadway running parallel until several hundred yards South of this bridge. The road continues North over this bridge and past the historic Lakewood farm. The railroad however splits and continues along the South/East side of the river to the town of Lakewood which was 2 miles East of the famous farm. The farm had it's own small redwood style watertower which resembled a tower for a steam locomotive which probably confuses things. But the train clearly didn't cross this bridge and went to the now long gone town instead. 1930's aerial pics also show this. Carefully read the article about riding the Bonnie Doon and it too agrees with the train going to Lakewood and then crossing the river a mile North of the town - 3 or 4 miles from this bridge site.
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