Explorers in Poland have begun digging for a legendary Nazi train laden with treasure – a train that may not be there, and may not even exist. According to local legend, Nazi forces sent 24 freight carriages from Budapest towards Germany filled with family treasures including gold, silver and valuable paintings seized from Hungarian Jews and estimated to be worth up to $200m (£154m).

Poland Nazi gold train
Workers begin excavations in Walbrzych, aiming to verify the existence of the so-called Nazi gold train Natalia Dobryszycka/AFP

The search attests to the power of a local legend claiming a Nazi gold train mysteriously vanished as the Germans escaped the advancing Soviet army at the end of World War II. It is believed the armoured train disappeared after entering a complex of tunnels under a castle in the Owl Mountains, a secret project known as "Riese" — or Giant — which the Nazis never finished. The tunnels do exist, but does the train?

Two amateur treasure hunters, Andreas Koper and Piotr Richter, said in August 2015 they had found evidence of the buried train. The two men claimed to have located it using radar equipment along the railway line between Walbrzych and Wroclaw. The area belonged to Germany at the time, but has been part of Poland since the borders were moved in the post-war settlement.

A government official initially said he was "99% sure" the train was there, but geological experts using magnetic equipment found no trace of it.

Polish authorities nonetheless are eager to check every possibility of recovering treasures that have sparked the imaginations of local people for decades. As the dig got underway, a yellow excavator could be seen moving earth along railroad tracks above the spot where two explorers believe the train is buried. Three separate sites inside a fenced-off area are being investigated.

"We have to find a railway track, probably the entrance to a railway tunnel and if the tunnel exists, there should be a train there," Andrzej Galik, a spokesman for the treasure hunters, told Polish media. "What do we expect? To unveil a sort of time capsule, something from that era, from the period of World War Two."

The work is expected to last several days. Historians say the existence of the train, which is said to have gone missing in May 1945, has never been conclusively proven. The team is expected to announce findings in the coming days.