A 40-YEAR caving dream to link three counties underground - creating Britains largest cave system - has become a reality after potholers made the final breakthrough from Yorkshire to Lancashire.

Nine cavers created the link at 4.30pm on Sunday after digging through tonnes of stone and rubble - making it now possible to travel between Cumbria, Lancashire and Yorkshire without breaking the surface.

The two teams of cave explorers broke through the final gap after 140m of tunnelling between the Lost Johns and Notts Pot caves in the Yorkshire Dales.

The breakthrough was the final piece of the jigsaw in a long-standing ambition to create the Three Counties Cave System.

Tim Allen, who along with a team of potholers has been connecting the final link for the last two years, said he was 'very excited' to be there when the breakthrough happened.

"All my time being involved within the caving community has been spent trying to link this system," said Mr Allen. "Cavers from all over the country have been congratulating us as it has been something known by cavers everywhere.

"Certainly above water it has been one of the most difficult and dangerous links to make."

Since the 1960s, hundreds of avid potholers have been exploring and digging to unite the network to achieve this system.

The combined total of the new cave system is estimated to be around 100km long- making it the longest in Great Britain.

Dave Brook, of the University of Leeds Speleological Association, first came up with the notion of uniting the caves in 1968 but back then it was considered more of a dream.

However, many different groups of cavers decided to give it a go and dots between the caves beneath Gragareth and Casterton fells started to be connected- with each passing decade new links being established.

And this is not the end, as although the system fulfils the dream of connecting the cave through the three counties, there are many possibilities for extending the cave much further into Yorkshire.