Photographer's notes: "Ironworkers fabricate rebar forms on the Arizona side, then the forms were transported via highline crane into position for the next segment of arch construction, June 29, 2009." Site Name: Mike O'Callaghan-Pat Tillman Memorial Bridge

Photographer's notes: "Evening view downstream from the Arizona side of the Black Canyon with the old crane platform (from Hoover Dam construction) below, June 29, 2009." Site Name: Mike O'Callaghan-Pat Tillman Memorial Bridge

Photographer's notes: "Aerial view of Lake Mead, Hoover Dam, and the bridge under construction with reflection of the bridge in river below, June 30, 2009." Site Name: Mike O'Callaghan-Pat Tillman Memorial Bridge

Photographer's notes: "Aerial view of the bridge, dam and Lake Mead." Site Name: Mike O'Callaghan-Pat Tillman Memorial Bridge

Photographer's notes: "Aerial view of a motor boat on Lake Mead near the mineral deposit banding that revealed the lower level of the Lake Mead reservoir, June 30, 2009." Site Name: Mike O'Callaghan-Pat Tillman Memorial Bridge

Photographer's notes: "Aerial view of bridge and the hairpin turn of the old Nevada road, June 30, 2009." Site Name: Mike O'Callaghan-Pat Tillman Memorial Bridge

Photographer's notes: "The dirt road leading from the Lower Access Road to the Hoover Dam Police shooting range plays off of the arch formed by the bridge construction, June 30, 2009." Site Name: Mike O'Callaghan-Pat Tillman Memorial Bridge