bar bars detail details fence fenced grating grille iron metal metallic safe secure security wire wire-fenced barbeb barbed wire countryside fields hills keep out post private sign warning appearance barbed-tape barbed-wire barbs barricade barrier danger double fencing gray grey injury protection razor-sharp razor-wire restraint security-fence sharp silvery spirals strands twists big cables chains construction heavy hook large rust rusty steel sundconst wires clouds conductor electricity grid high insulator power pylon sky tower transmission voltage amount chaos city civilization electric energy massive station traffic train autumn bird birds fishmonk flock group many perch season seasons silhouette silhouettes spring starling starlings winter