Simon Taffe was in the painting and decorating business when he decided to put on his own festival. It was 2005, and he was in the crowd at All Tomorrow’s Parties, the era’s zeitgeisty alternative music festival. “I drunkenly started writing out silly numbers about costs, literally on the back of a ripped-up cigarette packet,” he recalls. Taffe was 25 and had no experience in the music industry – but how hard could it be?

The question was: how far was Taffe prepared to go to get the first edition of End of the Road up and running? Sell his own house? Ask a mate to remortgage his? Rack up losses of nearly £500,000? The answer to all three questions was yes. “There were so many points we almost pulled the plug that first year because we were just losing so much money,” Taffe says. “There were a lot of people advising me to just walk away. I was too stubborn.”

End of the Road celebrates its 20th anniversary this year with a stellar line-up headlined by Pulp, CMAT and Mac DeMarco. With a capacity of just 13,500, it has long since been a jewel in the UK’s festival crown. It is much-loved for its independent spirit, carefully and personally curated eclectic line-up of music, comedy, film and literature, and picturesque, bespoke surroundings at Larmer Tree Gardens near Tollard Royal, Wiltshire.

But the festival was very nearly a grand folly. Lots of things went right, such as securing the gardens after a basic Google search for festival sites, and an impressive first-year line-up with Richard Hawley, Badly Drawn Boy and British Sea Power. In an early sign of the personal touch that End of the Road is famed for, Taffe and co-founder Sophia Hagberg would approach artists directly.

“We really hustled. We went to see bands during soundchecks and handed out personal letters with mixtapes of what we wanted to create. We flew to South by Southwest [in Austin, Texas] and made loads of personal contacts.”

Their naïve enthusiasm wasn’t universally popular. “We didn’t even know what agents were until we got a phone call from an irate agent telling us off for talking to his bands directly.”

But ticket sales were slow – “We were running competitions on MySpace and the radio, and letting everyone win just to get the numbers there” – and costs were spiralling. So Taffe sold his house for £140,000 and took out another £60,000 in loans. “I just thought, ‘I’m young enough. If I lose it all, I’m only 25 – I’ve done quite well already so I could rebuild’.”

But when that wasn’t enough, he asked a mate to remortgage his house. “I’m very lucky because about four months before, he asked to borrow £30,000 off me, and I lent it no problem. So I think he felt obliged.”

When he needed yet more money, they took out £100,000 in loans against the assumed early-bird tickets for the second year. “We were taking risks on that,” he says.

Inevitably, the run-up to the festival was a stressful time. “I wasn’t sleeping for the first week on site. I was like, ‘This is just gonna fail’.” One major worry was the weather. “If we’d had a washout, I don’t think we’d have gone into a second year.”

Luckily, despite terrible forecasts, it was overcast, and Taffe just about got away with it. “We only just had the right amount of numbers to make it an atmosphere.”

But reviews were good, and people enjoyed themselves, leading to a word-of-mouth buzz. The second year lost money too, but nowhere near as much. “About £70,000, but we knew we were on the up. By the sixth one, we were in profit.”

By the 10th edition in 2015, Taffe had left his painting and decorating company behind to do the festival full-time. It was so well established that bands were approaching Taffe to headline, as happened with Tame Impala.

That year, Taffe landed one of his dream headliners, the American singer-songwriter Sufjan Stevens: when he was announced, Stevens posted on Instagram the handwritten letter Taffe had sent him 10 years prior, first asking him to play. “It was amazing. The fact that he kept it for 10 years was impressive,” he says. “I guess it shows you what persistence will do.”

It also shows the community that End of the Road has cultivated. “It’s a place where bands want to play. And we always try and give the audience more than they expect. We have 70 per cent of people return, so that automatically creates a community vibe.”

Punters come back for a line-up that mixes the best old and new indie, folk, electronic and experiential artists. Taffe remains heavily hands-on. “I still choose every single band.”

The scenery is also a big draw. Larmer Tree is a Victorian pleasure garden with ancient woodland, ornate architecture and free-roaming peacocks, which is elevated further by art installations, drawings and sculptures that range from the whimsical to the Lynchian. “By year 12, the brand and the way it looks visually was how I originally intended,” says Taffe. “We’ve now got the finances to make it work.”

The Covid years aside, End of the Road has gone from strength to strength: so much so that the big corporations have been circling with offers. “It has never interested me,” says Taffe. “I always joke with them and say, ‘You can’t afford it, because it’s worth way more to me than you’.”

That’s a long way from losing £500,000. “I wouldn’t have imagined surviving for 20 years. I’m not really an anniversary person, but obviously it’s great to still be very successful.”

End of the Road takes place at Larmer Tree Gardens, Dorset from 3 to 6 September (endoftheroadfestival.com)