of multi-sign advertisements are no longer common, though they are not extinct. One example, advertising for the NCAA, depicts a basketball player aiming a shot on one billboard; on the next one, 90 yards (82 meters) away, is the basket. Another example is the numerous billboards advertising the roadside attraction South of the Border near Dillon, SC, along I-95 in many states. Many cities have high densities of billboards, especially where there is dense pedestrian traffic—Times Square in New York City is a good example. Because of the lack of space in cities, these billboards are placed on the sides of buildings and sometimes are free-standing billboards hanging above buildings. Billboards on the sides of buildings create different stylistic opportunities, with artwork that incorporates features of the building into the design, such as using windows as eyes, or for gigantic frescoes that adorn the entire building. Visual and environmental concerns Many groups such as Scenic America have complained that billboards on highways cause excessive clearing of trees and intrude on the surrounding landscape, with billboards' bright colors, lights and large fonts making it difficult to focus on anything else, making them a form of visual pollution - a state of affairs evoked pithily in Ogden Nash's parody of Joyce Kilmer's oft-quoted poem Trees: I think that I shall never seeA billboard lovely as a tree Indeed, unless the billboards fallI'll never see a tree at all. Other groups believe that billboards and advertising contribute negatively to the mental climate of a culture by promoting products as providing feelings of completeness, wellness and popularity to motivate purchase. B.U.G.A. U.P. was a movement which commenced in Australia and took direct action against primarily tobacco and alcohol billboards. Another focal point for this sentiment would be the magazine AdBusters, which will often showcase politically motivated billboard and other advertising vandalism, called culture jamming. Billboards have been criticized as an example of attention theft. In 2000, rooftops in Athens had grown so thick with billboards that it was difficult to see its famous architecture. In preparation for the 2004 Summer Olympics, the city embarked on a successful four-year project demolishing the majority of rooftop billboards to beautify the city, overcoming resistance from advertisers and building owners. Most of these billboards were illegal, but had been ignored until then. In 2007, São Paulo, Brazil instituted a billboard ban because there were no viable regulations of