autum fall hill leaves stairs stairway steps trees curved curves stairway decking exterior external railing rails sloping stainless steel timber wood wooden height high step top blue sky bright concept future metaphor open staircase unknown blue down industrial metal sky snail stell straight UP female friends friendship girl girls outdoors people slouds walk walking path pathway pavement elegant gold red red carpet upstairs architecture Denmark modern museum white brown cement country gargen green outside peaceful brick bricks upside wall