Hundreds of workers over the past few days have been toiling at the largest wrapping-and-decorating effort ever undertaken in Athens, involving dozens of acres of brightly colored banners, drapes and printed tarpaulins that will ornament streets, bridges and buildings during the August 13-29 Olympics. The operation, which is expected to be completed by the end of this week, will include a dozen illuminated helium balloons, 5 meters in diameter, which will fly above central Athens squares, at the entrance to the Zappeion Hall, on the Ermou pedestrian shopping street and in Koukaki. A total of 35 buildings in the city center are having their facades covered with vast tarpaulins printed with the work of Greek photographers, while up to 40 more building fronts will be hung with multicolored, king-size banners. In all, Athens 2004 organizers are having some 20,000 banners hung in the city center, mostly from streetlamps, 12 acres of tarpaulins on buildings, 23,000 meters of fabric ornamentation on bridges, and another 8,000 meters that will decorate gates and entrances to venues. A lower-scale operation is also under way in the four other Greek cities – Thessaloniki, Patras, Volos and Iraklion – where Olympic events are to be held.