The Parker through-truss bridge over the San Juan was built in 1937 as part of the WPA-era expansion of US 491. It carried all of the town's north–south traffic for sixty years; in 1997 a new concrete bridge took the through traffic and the old steel structure was kept for local use.
It is listed on the National Register of Historic Places. There's a small turnout on the south bank where you can stop and walk out to look at it — the riveted steelwork is photogenic, especially at sunset when the bridge glows orange against the desert.