Coordinates: 54°28′59″N 18°57′31″E / 54.48306°N 18.95861°E
Gdansk Bay or the Bay of Gdansk Polish: Zatoka Gdańska; Kashubian: Gduńskô Hôwinga; Russian: Гданьская бухта, Gdan'skaja bukhta, and German: Danziger Bucht) is a southeastern bay of the Baltic Sea. It is named after the adjacent port city of Gdańsk in Poland and is sometimes referred to as the Gulf of Gdańsk.
The western part of Gdańsk Bay is formed by the shallow waters of the Bay of Puck. The southeastern part is the Vistula Lagoon, separated by the Vistula Spit and connected to the open sea by the Strait of Baltiysk.
The bay is enclosed by a large curve of the shores of Gdańsk Pomerania in Poland (Cape Rozewie, Hel Peninsula) and the Kaliningrad Oblast of Russia (Sambian Peninsula). The coast of the bay features two very long sandspits, the Hel peninsula and the Vistula Spit. The first one defines the Bay of Puck, the latter one defines the Vistula Lagoon.