Greektown in Tarpon Springs was listed in 2014 on the National Register of Historic Places as a Historic District and Traditional Cultural Property for its unique ethnic heritage and maritime character. Bounded by the Anclote River on the north, Tarpon Avenue and Spring Bayou on the south, Hibiscus Street and Pinellas Avenue on the east, and Roosevelt and Grand Boulevards on the west, it grew from the transformation of Florida's sponge industry. In the late 19 century, black and white Americans, Bahamians, and Conchs worked in Tarpon Springs' new sponge industry, but in 1905 Greeks introduced sponge diving technology. Crews from the Dodecanese islands of Kalymnos, Halki, and Symi, and Sardonic Gulf islands of Aegina and Hydra learned of opportunities there, and by the end of that year 500 men had arrived. Within a few years, 100 sponge boats and up to 1,000 Greeks worked in Florida waters or related maritime businesses. Using both deep-sea diving and hooking techniques on boats with sails and engines, they revolutionized the business. Sponges became Florida's most lucrative sea product, and Tarpon Springs became the largest sponge port in the country. From 1905 to 1940, Greeks were the numerically dominant cultural group in Tarpon Springs and established Greektown, with residences, stores, churches, restaurants, coffee houses, and recreational facilities eventually stretching from the sponge docks to the city center. Because Greeks came to Tarpon Springs in relatively large numbers, they maintained an unusually large portion of their culture. After World War II, the sponge industry declined because of a massive sponge blight, and many residents sought other employment. Today, Greektown remains predominantly Greek American, with cultural identity reflected in occupations, language, foodways, buildings, religious practices, music, and dance. The district includes vernacular buildings such as St. Nicholas Greek Orthodox Church, St. Michael’s shrine, the Sponge Exchange and Sponge Docks, businesses and residences, and commercial industrial sponge packing warehouses from the early 20th century. Although Greek boat builders in Tarpon Springs built more than 200 sponge boats in the style common in the Dodecanese Islands, only three survive today.