Two treasure hunters began detailed tests Tuesday in the hope of revealing a fuller picture of a Nazi train they claim is buried in a hillside.
Piotr Koper and Andres Richter reignited decades of speculation in August when they announced they had located the train close to the town of Walbrzych, Poland.
According to local folklore, a train loaded with gold, jewels and weapons was hidden in a sealed tunnel by Nazi forces retreating from the advance of the Soviet Red Army in 1945.
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Koper, a Polish national, and Richter, a German, have already produced what they say is a rudimentary image of the train using ground-penetrating radar.
But now the trees above the site have been cleared, and the Polish military has checked the site for explosives, the treasure-hunting pair were set to carry out three days of more detailed scans.
The works were originally planned for Monday but rain meant the tests had to be postponed until Tuesday.
"We already know, namely, that under the earth there is a train. We need three days of good weather to carry them out," Koper told a press conference Monday.
The pair will use a metal detector, ground-penetrating radar, and a magnetometer, which is used to detect whether objects have magnetic fields.
"Now that the area is cleared of scrub these studies will be much more accurate," Koper added.
Local officials have suggested that because of the annual winter snowfall in Poland digging may not start until the spring.
Arkadiusz Grudzień, a spokesman for the local magistrate in Walbrzych, said "at the moment, we are focusing only on noninvasive testing stage." It was "too early to talk about extracting anything," he added.