Gdańsk is a city on the Baltic coast of northern Poland, and the capital of the Pomeranian Voivodeship. With a population of 486,492, it is Pola…Gdańsk is a city on the Baltic coast of northern Poland, and the capital of the Pomeranian Voivodeship. With a population of 486,492, it is Poland's sixth-largest city and principal seaport. Gdańsk lies at the mouth of the Motława River and is situated at the southern edge of Gdańsk Bay, close to the city of Gdynia and resort town of Sopot; these form a metropolitan area called the Tricity, with a population of approximately 1.5 million.