You'll be excited to know that Los Angeles is one of the few US cities that has full-motion digital billboards. In other words, you can run videos above several lanes of moving traffic (courtesy of WOW Media). You also get access to a large network of Train Stations across LA, as well as a range street-level signs (Urban Panels) to catch the eyes of the publicly transported - if that's how you roll. Oh, and there are Bus Shelters in Hollywood!
Notable vendors are Clear Channel Outdoor, Lamar, Intersection, Volta, and New Tradition (among others).
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