Getting your questions ready
Getting your questions ready
Beat the crowd
10 questions No timer
50 free Baltic Sea trivia questions with answers — geography quiz, new questions added Aug 2026.
Baltic Sea trivia for geography fans, cruise passengers, Nordic and Baltic expats and pub-quiz setters. The quiz starts with the basics - which nine countries touch the sea, where it drains, why its water is barely salty and why the shipworm leaves old wrecks alone - and then works through the gulfs, islands and straits: Bothnia and Finland, Gotland and Bornholm, Åland, the Curonian Spit, the Sound Dues once collected at Kronborg. History gets its share: Tacitus and Adam of Bremen naming the sea, Vikings calling it Austmarr, the Hanseatic League and its cogs, Sweden's dream of a Mare Nostrum Balticum, Peter the Great founding St Petersburg on the Neva, the loss of the Vasa in 1628, the sinking of the Wilhelm Gustloff in 1945 and the ferry Estonia in 1994, Cold War submarines, the Øresund Bridge, Nord Stream and the 'NATO lake' of the 2020s. Roughly a third of the questions are easy, a third medium and the rest will stretch anyone who did not grow up on its shores. Every answer has been checked against a reference page and each question shows its source once you have answered.
30 of 50 questions with answers and explanations. Play the quiz
Q 01How many countries have a coastline on the Baltic Sea?
Nine
Nine countries touch the Baltic: Denmark, Estonia, Finland, Germany, Latvia, Lithuania, Poland, Russia and Sweden; Belarus, Norway and others lie only in its drainage basin.
Q 02The Baltic is the world's largest basin of what kind of water?
Brackish
The Baltic is brackish: rivers draining an area four times the sea's pour in fresh water, while salt water can enter only over the shallow Danish sills, the Drogden just 7 m deep, so it stays fresher than the ocean.
Q 03Which sea does the Baltic drain into through the Danish Straits?
The Kattegat
The Danish straits open into the Kattegat, the shallow sea between Jutland and Sweden; only beyond it, through the Skagerrak, do Baltic waters reach the North Sea.
Q 04Which artificial waterway, opened in 1895 through Schleswig-Holstein, links the Baltic to the North Sea?
The Kiel Canal
The Kiel Canal, opened in 1895 as the Kaiser-Wilhelm-Kanal, runs 98 km from Brunsbüttel on the Elbe to Kiel-Holtenau, sparing ships a detour of roughly 460 km around Jutland.
Q 05What is the northern arm of the Baltic, lying between Sweden and Finland, called?
The Gulf of Bothnia
The Gulf of Bothnia runs about 725 km north from the Archipelago Sea to Tornio, with Sweden on its west shore and Finland on its east; its northern basin, the Bothnian Bay, freezes over every winter.
Q 06Which arm of the Baltic connects the sea to Saint Petersburg?
The Gulf of Finland
Saint Petersburg stands at the eastern end of the Gulf of Finland, where the Neva enters the sea; the city was founded there in 1703 on ground just taken from Sweden.
Q 07What is the maximum depth of the Baltic Sea, at the Landsort Deep on the Swedish side?
About 459 m
The Landsort Deep, southwest of Stockholm, reaches about 459 m, the Baltic's deepest point; the sea as a whole averages only around 55 m, which is why river runoff freshens it so easily.
Q 08Which Roman historian described the 'Suebic Sea' (Mare Suebicum), an early name for the Baltic, in AD 98?
Tacitus
Tacitus described the Mare Suebicum in his Germania of AD 98, naming it after the Suebi; Ptolemy later preferred 'Sarmatian Ocean'.
Q 09Which 11th-century German chronicler first called it the 'Baltic Sea', likening it to a belt?
Adam of Bremen
Adam of Bremen, writing around 1075, was the first to call it Mare Balticum, saying the sea stretched like a belt (Latin balteus) through the north; the name only became standard after 1600.
Q 10In German, Swedish, Danish and most other Germanic languages the Baltic is called the equivalent of what?
East Sea
German Ostsee, Swedish Östersjön and Danish Østersøen all mean East Sea; Estonian reverses it as Läänemeri, 'West Sea', while Finnish Itämeri keeps 'East Sea', a calque from Swedish.
Q 11What did the Vikings call the Baltic, a name meaning 'Eastern Sea' that appears in the Heimskringla?
Austmarr
Austmarr, 'Eastern Sea', is the name used for the Baltic in Snorri's Heimskringla, in a verse of the Ynglinga saga; Norse traders crossed it eastward to Gardariki, the lands of the Rus.
Q 12Which fossilised resin has been harvested on the Baltic's south shores since the 12th century?
Amber
Amber, the fossilised resin of ancient conifers, is mined and beachcombed along the southern Baltic; the Sambia peninsula in Russia's Kaliningrad region holds around 90 percent of the world's known deposits.
Q 13Which federation of merchant towns, grown from Lübeck, dominated Baltic trade from the 13th to 16th centuries?
The Hanseatic League
Q 21The ferry MS Estonia sank in September 1994 while sailing between which two cities?
Tallinn and Stockholm
The Estonia was sailing between Tallinn and Stockholm on the night of 27–28 September 1994 when the bow visor's locks failed in heavy seas; water flooded the car deck and she sank within about an hour, killing 852 people.
Q 22Why do old wooden wrecks such as the Vasa survive so well on the Baltic seabed?
The cold brackish water keeps out the shipworm
The cold brackish water keeps out the shipworm Teredo navalis, which bores through wooden hulls in saltier seas; that is why the Vasa, on the bottom off Stockholm for 333 years, was raised largely intact in 1961.
Q 23How far did the Swedish warship Vasa get into her maiden voyage in 1628 before she sank?
The Hanseatic League grew from Lübeck's 1241 pact with Hamburg into a network of some 200 towns; its Kontors in London, Bruges, Bergen and Novgorod enjoyed their own legal privileges.
Q 14What was the emblematic ship type of the Hansa merchants, depicted on its seals and coats of arms?
The cog
The cog, a single-masted, clinker-built trader with a flat bottom and high sides, appears on the seals of Lübeck, Stralsund and other Hansa towns; by the late Middle Ages it gave way to the hulk.
Q 15Which Latin phrase named the goal of Poland, Denmark and Sweden's 16th–17th-century wars for control of the sea?
Dominium maris baltici
Dominium maris baltici, 'lordship of the Baltic Sea', was the prize Denmark, Sweden and Poland fought over from the 1560s Northern Seven Years' War to the 1720s; Sweden held it longest, though Dutch ships carried most of the trade.
Q 16At which castle near Helsingør did Denmark collect its Sound Dues from ships passing through the Øresund?
Kronborg
Kronborg, rebuilt from the older Krogen fortress in the 1570s, guards the narrowest point of the Øresund at Helsingør, where Denmark levied the Sound Dues from 1429 until 1857; it is also Hamlet's Elsinore.
Q 17Which Russian ruler founded Saint Petersburg at the mouth of the Neva to secure a Baltic outlet?
Peter the Great
Peter the Great founded Saint Petersburg in May 1703 on the Neva delta, on ground captured from Sweden, and moved his capital there in 1712 to anchor Russia on the Baltic.
Q 18In the Crimean War, Russia's Bomarsund fortress was destroyed in which Baltic archipelago?
Åland
Bomarsund stood on Åland; an Anglo-French force captured and demolished it in August 1854, and in Finland the Baltic theatre is known as the Åland War. The fleet shelled Sveaborg off Helsinki in 1855.
Q 19Which German ship, sunk in January 1945, caused history's deadliest maritime disaster?
Wilhelm Gustloff
The Wilhelm Gustloff, packed with refugees from East Prussia, was torpedoed by the Soviet submarine S-13 on 30 January 1945; about 9,000 people died in the freezing Baltic, more than on any other single ship.
Q 20Which Soviet submarine commander sank the German evacuation ship Gustloff on 30 January 1945?
Alexander Marinesko
Alexander Marinesko, captain of the submarine S-13, trailed the Gustloff for about two hours, then swung round to attack from the landward side, where no escort expected a submarine; three torpedoes struck.
About 1,300 metres
Vasa had covered only about 1,300 metres of her maiden voyage on 10 August 1628 when a gust heeled her over, water poured in through the open gunports and she sank in Stockholm harbour; the inquiry punished nobody.
Q 24Since 1720, how many times has the Baltic Sea frozen over entirely, most recently in early 1987?
20
The Baltic has frozen over completely 20 times since 1720, the last in the severe winter of early 1987; in a typical winter only the Gulfs of Bothnia, Finland and Riga ice over, and even 2010–11 fell short.
Q 25Roughly what fraction of the Baltic Sea's surface is ice-covered at an average winter's peak?
About 45%
About 45% of the Baltic's surface freezes in an average winter, essentially the Gulf of Bothnia, the Gulf of Finland and the Archipelago Sea, with ice peaking in February or March; the Bothnian Bay freezes first and thaws last.
Q 26Which two seal species depend on the sea's winter ice, one of them breeding only on it?
Grey and ringed
The Baltic's grey and ringed seals both pup on the winter ice, but the ringed seal does so exclusively, rearing its pups in snow lairs on the ice, while the grey seal can also breed on skerries ashore.
Q 27What are the occasional pulses of salty, oxygen-rich North Sea water that flush the deep basins called?
Major Baltic inflows
Oceanographers call them Major Baltic Inflows: strong westerly storms push dense, oxygen-rich North Sea water through the Danish straits into the deep basins. Big ones came in 1993, 2003 and 2014, each reviving the anoxic central deeps.
Q 28Approximately what share of the Baltic seafloor is a variable 'dead zone' with almost no oxygen?
A quarter
Roughly a quarter of the seafloor, about 100,000 km², is a shifting dead zone: dense salty water lies trapped below the halocline, bacteria there release hydrogen sulphide, and fertiliser runoff feeding summer algal blooms makes it worse.
Q 29Which is Sweden's largest island, home to the Hanseatic town of Visby?
Gotland
Gotland, at roughly 3,000 km² Sweden's largest island, has Visby as its capital; the medieval town wall and warehouses earned it UNESCO World Heritage status in 1995, and it hosts Almedalen Week each summer.
Q 30Which Danish Baltic island is famous for its round churches and the fortress ruin of Hammershus?
Bornholm
Bornholm, far east of the rest of Denmark, has four medieval round churches and Hammershus, one of Northern Europe's largest castle ruins; Soviet troops bombed and occupied it in May 1945 and stayed until April 1946.