architecture spiral spiral staircase staircase stairs step metal metalwork monotone old past rusty spriral staircase bench climb concrete hill mountain park pavement stair walk construction corkscrew stairs flight of winding stairs grate grated helical shape shapes wentletrap winding stairs circular corner dark diffused-light gray grey handrail inside interior intricate light limited patterned patterns shadowy silhouette spiral-staircase spiraling spiralling steps structure sturdy turning turns window wrought-iron cast iron leaf leafs Nyberg spindle tree artist home house elegant gold red red carpet stairway upstairs brown buidling down museum UP