The UK’s deepest, longest and highest canal tunnel might also be its most haunted, according to the charity overseeing the site.
The Canal & River Trust (CRT) is marking 25 years since Standedge Tunnel reopened with a Halloween event promising to "scare even the most intrepid ghost hunter".
A crowdfunding appeal has also launched for a purpose-built trip boat for the tunnel, which stretches three-and-a-half miles along the Huddersfield Narrow Canal between Marsden in West Yorkshire and Diggle in Greater Manchester.
Finished in 1811 after 17 years of manual digging, it is recognised as one of the seven wonders of Britain’s waterways.
According to CRT, staff and visitors have reported strange lights, unexplained sounds and rumours of a mysterious robed figure.
Paranormal investigation groups have also explored inside the passage.
The initiatives mark a quarter-century since "the impossible restoration" brought the structure back into use.
CRT said that, since the canal’s restoration in 2001, thousands of visitors, school groups and families have travelled through the tunnel on the charity’s trip boat.
The vessel, though, has reached the end of its working life and the charity is asking for the public’s help to replace it.
As part of the 25th anniversary celebrations, CRT is organising a special Halloween boat trip into the darkness of the tunnel for spook-spotting activities on October 30 and 31.
The charity is also organising a series of other family ghost-busting activities along with Huddersfield Canal Society and the Friends of Standedge.
Catherine Clayton, area operations manager at CRT, said: “A trip through Standedge Tunnel is at the heart of the visitor experience, whether you’re joining us for a special event like Halloween or visiting at any other time of year.
“Without a replacement trip boat, future generations might not have a similar opportunity to experience this remarkable experience beneath the Pennines, which is why we’re asking for the public’s support.”
Tickets for the boat trips are available either in advance from canalrivertrust.org.uk or on the day from Canal & River Trust’s tunnel office in Marsden. The crowdfunder can be found at crowdfunder.co.uk/p/keep-standedge-tunnel-open-for-all
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