bridge frame launchpad metal metallic pad structure aged beam bulk endless endlessly grid handrail infinite iron metall metallic bridge no end off shore old old gateway path perspective rust rusty steel unlimited water way way to nowhere weathered background decay grunge industrial industry Portland rivet rivets Steel Bridge texture truss green ornate pedestrian railings span walkway London struts support big concrete large orange river wallpaper dark light Little Venice under crossing nature pilica spala spała trees cable circles construction filling force golden gate bridge irregular material pattern rods San Francisco strength suspension bridge