Its world-renowned tidal flats host unique marine life as well a thriving salt production industry. Sinan County includes more than 1,000 islands, about a quarter of all islands in the country. The majority are surrounded by shallow tidal flats that are alternately covered or exposed by the rise and fall of tides. The island also contains a salt museum and sea salt ice cream shop. Nicknamed the \"the purple islands,\" they are known for displays of purple paint on their buildings, roofs, phone booths, and bridge.