Drone pictures have revealed how the entrance to an ancient tin mine has opened up in the middle of a new £86m road opening next year. 

The huge fissure, measuring around 10m (32ft) long, was spotted on a stretch of land being turned into the new St Austell to A30 link road, in Cornwall.

It’s believed that the visible section of the roughly 3m (10ft) deep chasm is the sloped entry to an 'unmapped' former tin mine.

A black hole at one end of the crevice could be the start of the mine's shaft and go a long way underground.

It’s believed that the visible section of the roughly 3m (10ft) deep chasm is the sloped entry to an 'unmapped' former tin mine (Image: Paul Williams / SWNS) The new 3.9 mile road, which will become an arterial route through the Duchy, has been funded by both the local authority and the government.

But Cornwall Council said despite the surprise discovery, they didn’t expect the road’s completion date to change.

Their spokesperson said: “Given Cornwall’s rich mining history, it is not unusual for unmapped mining features to be discovered during the construction process.

“We have recently uncovered two features along the route and investigation works are underway to determine the best course of remediation.

“We do not anticipate any delays or additional costs as a consequence of this event and the road is still anticipated to be fully opened in spring 2025.”

The new road under construction (Image: Paul Williams / SWNS) Locals had been campaigning for the new link road as far back as 2014.

Steve Double, the since defeated ex-MP for St Austell and Newquay, said when the delayed road was announced in 2022 that it would be “vital” for the area.

He said: “Local businesses and residents have wished for a better connection to the A30 for many years.

“Previous schemes had been cancelled and there had been little prospect of this road ever being built.

Drone pictures reveal how the entrance to an ancient mine has opened up (Image: Paul Williams / SWNS) “I am delighted the road has now secured the final go-ahead from government and this funding represents the biggest single investment by any government in mid-Cornwall.

“It has been frustrating that the construction of this road has fallen two years behind the original plans, mainly due to the pandemic, but we have finally got there.

“This scheme will not only benefit St Austell and the surrounding area, relieving pressure on Roche, Bugle and Stenalees, but also provide huge economic.”