A Roman mosaic floor has been found beneath a vineyard that produces one of Italy’s most expensive wines.

After a century of searching, archaeologists have revealed yards of perfectly preserved tiles in the Valpolicella area near Verona, which is home to the prized amarone red. “What is emerging is the mosaic floor of a wealthy villa from the 3rd or 4th century AD, with illustrations of chariot races and intricate geometrical designs,” Gianni de Zuccato, one of the archaeologists, said.

Experts now hope to excavate all the mosaics, which are thought to cover 300 sq m, and open them to the public. The villa was first uncovered in 1887 and excavated in 1922 but it was later reburied and no information was left about its exact location.

“Archaeologists at the time took photos, but I believe they ran out of money and fell foul of the landowner,” Mr De Zuccato said. “The trouble is [they] didn’t leave a proper record of where the mosaics were.”

Subsequent owners of the land have also proved reluctant to allow digging in an area where grapes are grown for amarone, which sells for £200 a bottle. “The land is as valuable as gold,” said Mr de Zuccato, who works for the archaeological inspectorate of Verona.

He won permission to search for the site again after noting that new buildings were going up in the area. “We needed to find it or lose it for ever,” he said.

He was backed by the local mayor, Roberto Grison, who said: “It didn’t help that five sisters currently own that land and it was hard to get them to agree.” Permission was granted, however, allowing trenches to be dug between the vines, exposing the mosaic which lies 80cm to three metres below ground.

The prospects of finishing the excavation are now good, Mr De Zuccato said, adding: “The sisters are selling the land and the buyer is an enlightened person who has committed to allowing us to dig and open to the public.”