A municipality worker in Germany found eight gold bars while mowing a stormwater retention basin.
After he reported the find in Bannetwitz, south of Dresden, officials discovered two more bars, with police valuing the hoard at well over €30,000 (£26,500).
Each bar weighs once ounce, reports local broadcaster MDR.
Investigators, who confirmed the discovery on Friday, are trying to determine whether the bars were stolen in burglaries or fraudulent crimes.
So far, they do not appear to be linked to any existing cases. Engraved serial numbers will be used to determine the rightful owner of the gold.
The bars are currently being held at a secure location at the Dresden Police Headquarters.
Marko Laske, spokesperson for the Dresden Police, told said: ‘I’ve never encountered a case like this in over 20 years.
‘The fact that gold bars are turned in to the police as found property is extremely rare.’
If no owner comes forward within six months and police determine no crime has been committed, the find will be handed back to the municipality.
The municipality can then decide what happens next.
Bannetwitz mayor Heiko Wersig said if the money were given to the town, he would like to see it awarded to clubs in the area.
He said he ‘could hardly believe it’ when he first heard about the discovery.
Last week, Metro reported on a man who sent a £10,000 gold to the Royal Mint only to find it had been lost by Royal Mail.
Rob Hobson had bought the 100g gold Britannia bar from his dad’s inheritance and had agreed a buyback offer from the Royal Mint after it was valued at £9,731.
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