The Hereford Bridge is one of the last actively used one‑lane bridges in southern Arizona. / Photo by Google Via Google Maps Street ViewEarly ConstructionAccording to the National Register of Historic Places, the Hereford Bridge was built in three phases between 1912 and 1927. RELATED: Exploring The San Pedro Riparian National Conservation AreaPhoto by Harley Noble/TSM Photo by Harley Noble/TSMThe Bridge TodayThe bridge reopened in 2006, keeping its original one-lane design. Widening it would have required major environmental disturbance along the San Pedro River and would have erased one of Arizona’s last surviving early truss bridges. It is also an access point for the Hereford Trailhead, on the south side of Hereford Road, just east of the bridge.