Photograph of the Colorado Street Bridge, looking northwest, Pasadena, ca.1915-1920. The trusted deck arch bridge appears to be in the late stage of its construction. At the left end of the bridge are construction machinery. An undeveloped part of the mountain (at left) blocks the road and the bridge from connecting. Midway across the bridge hangs two signs which reads: "Mercereau Bridge & Cons Co. Contractors", "Riverside cement used". Street lamps line the bridge. Nearby the bridge are several residential houses. A two-story house is clearly visible in the foreground. Also in the foreground is a road sign that reads "private grounds".