The Vistula Lagoon (Zalew Wiślany) is a brackish water lagoon on the Baltic Sea 90 km (56 mi) long, 10 to 19 km (6 to 15 mi) wide, and up to 17 feet (5 m) deep. It's separated from Gdańsk Bay by the Vistula Spit.
READ: Cult of the Fire God - Bronze Age Quest Adventure
The sand spit is narrow, a few hundred meters wide on average. The widest point is 1.8 km (1.1 mi). About 70 km (43 mi) long, it consists of marine sand dunes up to 50 m (164 ft) high. Average sand height are 10 - 20 m (32.8 - 65.6 ft)
READ: Lora Ley Adventures - Germanic Mythology Fiction Series
The spit is considered stable. Two canals lead through into the sea, one in Russian territory. The other is the new Nowy Świat Canal in Poland, between villages of Skowronki and Przebrno. In extreme winters the lagoon freezes for about four months.
A number of fish inhabit the Vistula Lagoon. They include perch, bream, northern pike, zander, sea trout, sturgeon, flounder, herring and cod. The waters of the Vistula Lagoon are saltier than those in the adjacent Curonian Lagoon.
READ: Cult of the Fire God - Bronze Age Quest Adventure
Some fish such as northern pike, a freshwater species, show tolerance to the salinity of the Vistula's brackish water. The region is a member of the Natura 2000 network of protected areas covering Europe's most valuable and threatened species and habitats.
The Vistula river originates in the Barania Góra Mountains in SW Poland and flows north. The Vistula (Wisla, Vistule, Weichsel) River Basin has a drainage area of 193,894 km2 and covers almost 60% of Poland. Upon reaching the Baltic delta it splits into six distributaries.
The lagoon is shared between Poland and Russia's Kaliningrad Oblast. Before the 2022 inauguration of the Polish Nowy Świat or Vistula Spit canal, the only water route from the lagoon out to Gdańsk Bay is the Strait of Baltiysk in Russia.
The Vistula Lagoon is considered part of Gdansk Bay, which dips in a long graceful arc to form a natural curve in the Baltic Sea. Branches of the Vistula River flowing into the lagoon include Nogat and Szkarpawa. Nogat is the most significant distributary.
Along the Nogat is an impressive castle of the early Middle Ages, built by the Teutonic Order (Teutonic Knights) of Malbork in the 13th century. The Teutonic Knights, a German Catholic society, destroy the Old Prussians from this stronghold.
Frombork, Poland is a small port on the lagoon with a 14th century Gothic cathedral. It's the home of Renaissance polymath Nicolaus Copernicus (1473 - 1543), who is the first to place the Sun at the center of the universe.
READ: Cult of the Fire God - Bronze Age Quest Adventure
The Frombork region is an important bird area of Poland. Birds include smew, greater white-fronted goose, bean goose, northern pintail, tufted duck, common pochard duck and little gull. It's an area favored by birders due to many migrational bird species.
Three phytoplankton groups dominate in in the Vistula Lagoon - cyanobacteria, green algae, and diatoms. Blooms are observed June to September in the central part of the lagoon. Toxic cyanobacteria blooms have also been observed regularly in the Russian part.
READ: Lora Ley Adventures - Germanic Mythology Fiction Series
Small blooms of green algae are normal and provide abundant food for aquatic animals. As blooms grow they block out sunlight and suck the oxygen from the water, killing fish and other water life, as well as the ecosystem around them.
Almost the entire Vistula river fails to meet water quality standards and swimming is not suggested, also due to unseen undercurrents. Boating is allowed. The Wloclawek Dam, constructed 30 years ago, is a toxic trap for much of the waste discharged into the river.
READ: Reiker For Hire - Victorian Detective Murder Mysteries
The lagoon is also an outlet for the Pregolya River. The Polish port Elbląg is an influential shipping and trading center in the past. Today silting and international cooperation issues have depleted its influence.
Silting occurs naturally, forming the beautiful deltas at the mouths of streams or rivers. From the highlands, rivers bring fertile silt and minerals into the delta. In this type of environment, civilizations such as Mesopotamia and Egypt are born thousands of years ago
In the Vistula Lagoon an island of silt is created by humans from the inflow of the rivers. According to analytic sources the silt on the Polish side of the Vistula Lagoon is well suited for fortifying beaches and island-building.
The history of Elbląg dates back to 1237, when the Teutonic Knights builds a fortified stronghold on the Ebling River. The purpose of the citadel is to prevent resettlement of Old Prussian site Truso, as the German crusaders are at war with the pagan Prussians.
READ: Lora Ley Adventures - Germanic Mythology Fiction Series
The castle becomes the official seat of the Teutonic Order Masters. Elbląg joins the Hanseatic League, increasing its status and prosperity.
Founded by north German towns and merchant communities abroad, the League protects mutual trading interests. It dominates commerce in north Europe from the 13th to 15th century. From the first half of the 13th c. the lagoon is part of the State of the Teutonic Order.
READ: Reiker For Hire - Victorian Detective Murder Mysteries
In 1454, King Casimir IV Jagiellon incorporates the region into the Kingdom of Poland, as requested by the anti-Teutonic Prussian Confederation. The 1466 Peace of Thorn (Toruń) of is a treaty signed in Hanseatic city Thorn between King Casimir IV and the Teutonic Knights.
The signing of the treaty ends the Thirteen Years' War, the longest of the Polish - Teutonic Wars. Afterward, the lagoon remains part of Poland. In the West is the Polish province of Royal Prussia and Greater Poland.
READ: Lora Ley Adventures - Germanic Mythology Fiction Series
The east is a Polish fief, held by the Teutonic Knights and Ducal Prussia. The surrounding area is inhabited by Poles, Germans and Kursenieki.
After the First Partition of Poland in 1772, the territory forms part of the Kingdom of Prussia. Prussia becomes part of the German Empire in 1871.
READ: Reiker For Hire - Victorian Detective Murder Mysteries
The earliest version of the name of the Vistula Lagoon is recorded in historical sources as Estmere by trader and traveler Wulfstan of Hedeby at the end of the 9th century. It's an Anglo-Saxon rendition of Aīstinmari, the Old Prussian name for the lagoon.
The name merges two Old Prussian words: Aiste and *mari meaning "lagoon". This oldest known meaning of the name is "the lagoon of the Aesti", a Baltic Germanic group. The Old Prussian name is still used in Lithuanian as Aistmarės to maintain original meaning.