In the six years since Jan Wilkinson lost her partner, Mark Weir, in a helicopter accident there have been plenty of good and bad times at Honister that she’s wanted to share with him.

I ask Jan if there’s one occasion that stands out but realise too late that it’s a crass question: “One? No, there’s thousands,” she says. “Every day, it didn’t matter if he was back at two o’clock or four o’clock in the morning, we would have a chat.”

They would talk about what had happened during the day at Honister, the working slate mine at the top of Honister Pass that Mark had bought and reopened in March 1997 – welcoming visitors for the first time – and about which he was passionate.

The conversation would continue the next morning over breakfast at their home, near Loweswater, and Mark would see their three children, Prentice, Piers and Georgie Blue, off to school before heading back to Honister, often in his Gazelle helicopter.

That happy family life was brought to an abrupt end in March 2011 when Mark died, aged 45, in an accident when his Gazelle craft crashed not far from the mine.

A charismatic figure, he’d become well known for promoting Honister and the Lake District and for battling with the authorities over developments at the site.

His ambition to construct a zip wire for visitors to zoom down from the summit of Fleetwith Pike was the most controversial and proved a divisive topic in the Lake District.

Until Mark’s death, Jan, 51, had been a full-time mum who helped out with the business accounts. But after losing Mark, she had to step up to run the attraction, alongside his brother, Joe Weir, and with help from his mum, Celia Taylor-Weir.

Jan and Joe and their 20-strong team – they employ 26 people during the peak summer season – have kept Honister a busy place that attracts approximately 110,000 visitors a year, who want to find out more about England’s only working slate mine, take an underground tour, or experience the adrenalin rush of the high rise Via Ferrata attractions and the dizzying Burma-style Infinity Bridge, the longest of its kind in Britain.

Alongside the visitor side of the business, Joe heads up a team producing high quality Westmorland Green Slate, just as men did for hundreds of years before the mine was closed in the late Eighties.

Having several strands to the business has served them well and was vital following the floods of December 2015, when visitors couldn’t get to Honister. Jan says the problems were offset by strong demand for walling slate to rebuild bridges on the damaged A591 and in other projects.

“When we had the floods, people just couldn’t get here and that was difficult for us. But the wonderful thing about this business is we have different income streams and we supplied some walling stone for the bridges on the A591,” she says. “Over the course of the year we balanced out.”

This month marks Honister’s 20th anniversary and the team has developments in the offing to keep things fresh.

A one-man play, The Professor of Adventure , about the Borrowdale cave-dweller Millican Dalton, is to be staged on Thursday (on what would have been his 150th birthday), followed on May 6 by string music from the Modulus Quartet. Both events will be held underground in the mine.

There are plans to link with Mountain Goat and The Lakes Distillery to offer combined tours. Meanwhile, Honister’s Infinity Bridge, a Burma-style bridge constructed 2,000ft off the ground – so called because it’s often impossible to see the end – is to be offered to newlywed couples as a location for photoshoots, along with the surrounding landscape.

Jan says couples wearing their wedding clothes would pose on the perilous-looking bridge for unique and stunning pictures: “Wouldn’t it be good to have a reason for the bride and groom to get the dress back out and come on their first anniversary and get an iconic shot? They’re not going to get that shot anywhere else in the world.”

To complement the photography shoots, Keswick jeweller Brian Fulton is designing a range of jewellery, including rings, bracelet charms, earrings, necklaces, cufflinks and lapel pins, combining Honister slate with metals.

Mark’s impromptu decision to buy Honister happened when he took his grandfather, who had once worked at the mine, on a helicopter flight over the site. He worked flat out to make it a success and he became a major figure in tourism in Cumbria.

His arguments with the powers that be brought him to national attention and he took part in a BBC4 documentary about the zip wire. I ask Jan what Mark would make of how they have developed the business.

“He would be happy that we’re still here because he loved Borrowdale and he loved the Lake District, he was very proud of his roots,” she says.

But she says that he would also be fed-up at the lack of progress on projects such as the zip wire: “He was massively frustrated about us being held back, as we are, but we’ve not given up on all that we want to do.”

The Lake District National Park Authority has twice turned down the zip wire but Jan says the idea hasn’t gone away and is still on the back burner.

Jan and Joe have visited Zip World in North Wales, where she says they employ about 80 people, and tried out one of the zip wire rides. It’s an example, she says, of a vibrant place offering job opportunities where visitors can break out of their everyday routines and be more adventurous.

At Honister, Jan says the Via Ferrata – the Italian name means iron walk way – has grown in popularity every year, but that the original Via Ferrata Classic has been outstripped by Via Ferrata Xtreme – a challenging guided mountain ascent described as having edge exposure, vertical climbs, cliff edge ladders, a cargo net and its own Burma bridge.

Jan loves seeing a family bond over completing the Via Ferrata, when the parents are taken out of their comfort zones and teenagers have to leave their phones behind – because they inevitably drop the devices and then want the guide to pick them up.

People’s facial expressions tend to say it all: “On the Via Ferrata you see fear, you see achievement, you see happiness. They get to the top and mum and dad are more than happy they’re still alive. They get the achievement and they get the beautiful vista.”

They’ve also come together as a family, talked and created memories and will likely want to come back to the Lake District and Honister.

Jan has now dropped back to a part-time job at Honister, taking the supporting role which she says suits her better. Her priority has always been her children. Prentice is now 20 and studying for a degree in international business, marketing and management at Manchester; Piers, 18, is an apprentice mechanic at a garage in Cockermouth; and Georgie Blue, 15, is at Cockermouth School.

Jan would be happy to see any of them work at Honister – along with Joe’s three children – but wants them to experience life elsewhere first and to decide for themselves that they want to come back.

They would also have to make a contribution to the business and start on the bottom rung: “It would be only if they bring something to the table.”

Jan’s aim this year is to get fit ready for a charity challenge. Before she met Mark she’d done a lot of travelling and lived in Brazil.

She’s returning to the country in October to take part in a five-day bike ride, aiming to cover about 75 miles per day and raise £3,000 for women’s cancer charities.

Active and busy – she’s often to be found dealing with maintenance issues at her holiday cottage business – she remains a glass half full character, grateful for the years she knew Mark: “We had 30 years together and the effects of having him in my life are still with me every day.”

She still finds Honister an inspirational place and hopes they’ve done worthwhile work over two decades, creating secure jobs and helping to publicise the Lake District internationally.

“I genuinely believe that we’re just caretakers. We’ve been looking after this place, with Mark, and I think we’ve made mistakes but we’ve shown we’re profoundly proud of being here and actually care about how we can optimise our time at Honister for Cumbria and the Lake District.”