A historic steam tugboat that sank more than 80 years ago has emerged from shrinking waters in Serbia as extreme heat and drought grip Europe.

The rusting hull of the Slovenian surfaced earlier this month from the Sava River near Sremska Mitrovica, about 70km northwest of the Serbian capital Belgrade.

WATCH THE VIDEO ABOVE: Century-old wartime shipwreck emerges in Serbian river

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Parts of the wreck have appeared above the water before, but locals say it has never been so exposed.

“It’s been several years since it was last seen, so there is quite an interest,” said historian Andrija Popovic, who is the head of the town museum.

“It’s truly something you don’t see every day,” he added about the boat, which has been dubbed “Sava’s Titanic” by Serbian media.

Its reappearance is among a series of extraordinary discoveries emerging from Europe’s rapidly shrinking waterways, with warships, mammoth bones and ancient structures exposed as river levels plunge.

Record-low levels on the Danube have severely impacted nuclear power plants in Hungary and Romania and disrupted traffic along Europe’s second-longest river.

The months-long drought has also ravaged crops from the Netherlands to Bosnia and caused water shortages extending into the Alps.

The ship survived two World Wars before it sank

The Slovenian was built in a Budapest shipyard in 1913, when Hungary was part of the Austro-Hungarian Empire.

The roughly 54m-long steam-powered vessel was initially named Vag, after Slovakia’s longest river, the Vah, and was used to pull heavy cargo between Budapest and other towns along the Danube.

Its routes were largely suspended during World War I.

After the war and the collapse of the Austro-Hungarian Empire, ownership was transferred as part of war reparations to the newly formed Kingdom of Serbs, Croats and Slovenes, which would later become Yugoslavia.

“This is when it was renamed the Slovenian,” Popovic said, adding that it’s a mystery “why this name was chosen.”

During World War II, the vessel came under Nazi German occupation along with Yugoslavia.

After Yugoslav anti-fascist forces liberated Belgrade in 1944, the boat was used to transport wounded fighters and equipment as German troops were pushed west.

The Slovenian was carrying wounded fighters when it struck a German mine in late April 1945.

“It sank and has stayed in the same place since that day.”

A shrinking Danube surrenders German ships and mammoth bones

The Slovenian is not the only relic that has emerged from Europe’s drying rivers.

Along Serbia’s eastern border with Romania, the rusting remains of German ships have appeared from the receding Danube.

Some are still laden with weapons and belonged to Nazi Germany’s Black Sea fleet, which was deliberately sunk near the end of World War II as German troops retreated from Romania and Soviet forces advanced across Europe.

In Italy, severe drought has exposed the piers of an ancient bridge over Rome’s Tiber River that was once used by Roman emperors before falling into disrepair by the third century.

In Bulgaria, shrinking Danube waters have also revealed the remains of an extinct woolly mammoth.

Researchers recovered a jawbone, tusks, shoulder blade, ribs, and other fragments that had been buried deep in the sand.

Experts seek ways to prepare for more extreme weather

Europe is the world’s fastest-warming continent, with temperatures rising twice as fast as the global average since the 1980s, according to the European Union’s Copernicus Climate Change Service.

By late July, half of the European Union and the United Kingdom was experiencing drought, according to the EU’s European Drought Observatory, with 9 per cent of the territory at the most severe “alert” level.

Scientists have warned climate change is increasing the frequency and intensity of extreme heat and dry conditions.

Serbian hydrology expert Dejan Vladikovic said the current drought was the result of a lack of winter snow combined with an extremely dry spring.

“What awaits us in the future ... is that such situations will be more frequent,” he said.

“We are entering periods when this will, unfortunately, become a new normalcy.”

Even mountain regions are struggling with water shortages.

In the Slovenian Alps, lodges dependent on rainwater have restricted water use for climbers and hikers, including showers and toilets.

Triglav Lodge, Slovenia’s highest-altitude guest hut at 2515m, has resorted to using paper plates this summer to conserve water otherwise needed for washing dishes.The Triglav Lodge, Slovenia’s highest-altitude guest hut at an elevation of 2,515 meters (8,251 feet), is using paper plates this summer to save water on dishes.

- AP