Bay of Riga

Gulf of Riga
Location in Northern Europe.
Location	Europe
Coordinates	57°45′N 23°30′E / 57.750°N 23.500°E / 57.750; 23.500Coordinates: 57°45′N 23°30′E / 57.750°N 23.500°E / 57.750; 23.500
Primary inflows	Daugava, Pärnu, Lielupe, Gauja, Salaca
Surface area	18,000 km2 (6,900 sq mi)
Average depth	26 m (85 ft)
Max. depth	67 m (220 ft)
Water volume	424 km3 (344,000,000 acre·ft)
Residence time	30 years
Frozen	Most or all during winter
Settlements	Riga, Jūrmala, Pärnu, Kuressaare, Salacgrīva, Saulkrasti, Ainaži

The Gulf of Riga, Bay of Riga, or Gulf of Livonia (Latvian: Rīgas jūras līcis, Estonian: Liivi laht, Russian: Рижский залив) is a bay of the Baltic Sea between Latvia and Estonia.

The island of Saaremaa (Estonia) partially separates it from the rest of the Baltic Sea. The main connection between the gulf and the Baltic Sea is the Irbe Strait.

The Gulf of Riga, as a sub-basin of the Baltic, also includes the Väinameri Sea in the West Estonian archipelago.

The International Hydrographic Organization defines the Gulf of Riga's western limit as "A line running from Lyser Ort (57°34'N), in Latvia, to the South extreme of Œsel Island, through this island to Pammerort (22°34'E), thence to Enmast Point, the S extreme of Dagö, through Dagö to Takhkona Point, the North extreme thereof, and on to Spithamn Point in Estonia".

Major islands in the gulf include Saaremaa, Kihnu and Ruhnu, which are all controlled by Estonia. Kihnu covers an area of 16.4 square kilometres (6.3 sq mi). Saaremaa island is responsible for the brackish water of the Gulf of Riga, as it is partially "shielded" from the Baltic Sea.

Notable cities around the gulf include Riga, Pärnu, Jūrmala, and Kuressaare. The main rivers flowing into the gulf are Daugava, Pärnu, Lielupe, Gauja, and Salaca.