The coins were found in 19 amphoras, a type of Roman jug, in Tomares, a town in Seville province.
Lola Vallejo, Tomares urban councillor, told CNN-affiliate Atlas that a crew had been digging a ditch to install electricity to a park when they came across the incredible find.
“The machines hit against something that wasn’t normal for this soil,” Vallejo said. “The workers immediately stopped, and soon discovered that there were many coins there, inside broken amphoras.”
“What is incredible is a discovery of this size — there are 19 amphoras, all complete, and I can assure you that they can’t be moved by one person alone, because they weigh so much due to the coins inside,” said Ana Navarro, head of the Archaeology Museum in Seville.
“Ten of (the jugs) were broken while they were digging up the trench, and the others, as you can see, we have here, whole and full of this set of coins,” she said.
The initial hypothesis is that the coins were to be used to pay taxes to the Roman empire, according to Spanish newspaper El Pais.