A group of Russian history buffs was surprised to find a reminder of Soviet resistance to the Nazi invasion in the form of an improvised minefield near a busy road.
Members of a club devoted to the history of the nearby Krasnaya Gorka military fort almost stumbled across the makeshift mines in a quiet stretch of woodland not far from St Petersburg, the local Kanal 5 TV channel reports.
Club chairman Alexander Senotrusov said Soviet forces stationed at Krasnaya Gorka had no mines with which to block German tanks on their way to Leningrad in 1941, so they improvised explosives from pre-revolutionary naval shells and laid them out in rows around the fort.
"One pound of pressure, and up you go," he told Kanal 5.
"It's a miracle that there's not been a tragedy here in nearly 80 years," marvelled TV correspondent Roman Ishmukhametov as he stood alongside a mine - all the more so as local people have been coming across occasional shells for seven years while out mushroom-picking.
He said the soldiers who laid out the explosive devices had either died in the war or been posted elsewhere, and the extent of the minefield was gradually forgotten.
Mr Senotrusov informed the police, but the officer who arrived had to be guided out step by step after accidentally wandering into part of the minefield. So they decided to call in the army.
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The defence ministry owns the land either side of the A121 highway by the turning to the village of Lebyazhye, as it is close to the fort. Military records suggest that the defenders of Krasnaya Gorka laid about 400 improvised mines in five rows in a 120-metre (394-foot) strip.
Teams of sappers with metal detectors have so far found 64, the local Kanal 47 TV channel reports.
The bomb-disposal specialists have tried to allay local suspicions that the shells might still be volatile, and are sure that the improvised trigger mechanisms have largely rusted away.
Nonetheless, the troops told Kanal 47 it may take a week before it is safe for the public to go down to the woods again.
Reporting by Damien Sharkov and Martin Morgan
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