This stone pier was put in by the Denver,South Park and Pacific RR in about 1880. You missed 2 other bridges that were old RR bridges that have been replaced with "modern" bridges. One is on CR162 just east of Mt. Princeton Hot Springs and the other is on CR290 just after it leaves CR162 just west of Deer Valley Guest Ranch. Both of these bridges are on the DSP&P bed and on the original stone. A company called Model Masterpiece had a HO scale modle kit of the Chalk Creek bridge and it is the one on CR290. I remember this a a 2 truss bridge before it was replaced. The county did it to preserve their grants, not because the bridge was bad.