ISTANBUL — The fourth "Istanbul Shopping Fest" opened on Friday to extravagant sound, light and dance performances.The Shopping Festival, which will continue until June 29, is organized by the Istanbul Chamber of Commerce, the Turkish Federation of Shopping Centers and Retailers (TAMPF), The Association of Turkish Travel Agencies and Istanbul Metropolitan Municipality Culture, Inc.The inauguration ceremony saw a British Flyboard group "Water Rockets" perform an extreme high-flying, jet-powered show, complete with fire, pyrotechnics and lasers, over the Sea of Marmara.Varied street fairs, concerts, demonstrations, children's games, parties, competitions and fashion shows will be held for 23 days by different performers. Various discounts will also be offered to costumers during the festival.