New Mexico Route 66 - Rio Puerco

The steel truss Rio Puerco bridge has a concrete deck resting on steel stringers, built to withstand the river below which had a habit of washing away lesser bridges. It was completed in 1934 and carried traffic until it was replaced in 1999. You can walk across it now, with the busy interstate bridge on one side of you, and the calmer replacement Route 66 bridge on the other.