Saw this on the 580 by Grand Lake. Banner is about 70 feet long, handpainted on Tyvek house wrap. Story here.
Bungee Cord Mounting: Place sign against fence, stretch bungee cords across it.
Ledge/Wall Mounting: Fold boxflaps over wall, put rocks on top.
Hammer and Nail Mounting: Place cardboard against wooden surface. Hammer in nails.
Signs placed on the 80, 580 and 880 Interstates in Berkeley, Oakland and Richmond. Most have been up for three days and counting. Signs placed on overpasses will generally survive for a few hours, while those placed on fencing alongside the roadway can stay up for weeks.
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