Zelzate is a municipality located in the Belgian province of East Flanders. The municipality only comprises the town of Zelzate proper. In 2021, Zelzate had a total population of 13,124. The total area is 13.71 km2. Zelzate is divided into two parts by the Ghent–Terneuzen Canal. There is a concrete drawbridge and a tunnel to connect the two sides. Zelzate is known for the nearby polluting industry, which makes it the village with the lowest air quality in the country.