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From novice to ultrarunner: Hannah Cox's 4,200km journey
Hannah Cox, a 41-year-old from Manchester, ran 100 consecutive marathons across India in 100 days, tracing a historic colonial-era route. The challenge, dubbed Project Salt Run, raised funds for environmental charities and became a deeply personal tribute to her late father.
The route and the resolve
Cox's journey followed the Great Hedge of India, a 4,200km customs barrier established by the British in the 19th century to enforce a salt tax. Inspired by her Indian heritage and her father's birthplace near Kolkata, she set out from the Attari-Wagah border with Pakistan on October 26, 2025, aiming to finish in Kolkata.
Before the challenge, Cox had never run seriously. She joined a local running club in 2024, progressing from 5Ks to back-to-back marathons in the UK to prepare. "Everyone tried to put me off at first-people just didn't believe I would actually do it," she said.
Dust, danger, and determination
The physical toll was immense. Cox battled extreme heat, dust, and smog, losing over 10kg despite consuming 6,000 calories daily. Her diet consisted of porridge, rice, eggs, and roadside curries, often prepared in her support van. She ran through nature reserves, highways, and regions prone to tiger attacks, requiring police escorts at times.
Road hazards were constant. "There were cows, snakes, and goats in the road, and drivers regularly traveled on the wrong side," she recounted. A collision with a motorbike left her with a scar on her leg. Her patched-up trainers, reinforced with pieces of a car tire, became a symbol of her resourcefulness.
Sickness and surreal encounters
Illness struck repeatedly. On day 24, Cox met Richard Branson at the Taj Mahal while battling food poisoning. "I was sick all day by the side of the road but I just knew I had to finish," she said. Branson's team later joined her for a marathon, running alongside her despite her condition.
Her support crew-a driver, a helper, a podiatrist, and a fellow runner-kept her going. The van served as her mobile home, with cold showers and roadside laundry becoming routine. Every 10 days, they splurged on a cheap hotel for a hot shower.
Fundraising and financial strain
Cox aimed to raise £1 million for environmental and social impact charities. While she hasn't yet reached the target, she remains committed. "The project wouldn't have worked without the grassroots support and community aspect," she emphasized.
Financially, the challenge took a toll. Personal loans were renegotiated mid-journey as funds dwindled. "I'm still trying to recoup the costs," she admitted.
Psychological keys to endurance
Sports psychologist Amy Whitehead highlighted the three pillars of Cox's success: autonomy, social support, and competence. "If you've got those, you can succeed," Whitehead said.
Cox's approach was pragmatic. "Run 15km, eat, run 15km, eat, run 12km, eat, sleep, repeat," she described. Her feet emerged unscathed, a testament to her podiatrist's care and her own resilience.
A love letter to her father
For Cox, the journey was more than a physical feat. "Project Salt Run felt like a very, very late love letter to my dad," she reflected. "I had a complicated relationship with him, but this was my way of connecting with my heritage."
Since completing the challenge, she has run the Brighton and London Marathons, though she found the UK races more intimidating. "In India, it was me and my friends with a core mission. Here, it felt like a performance space," she said.
"The universe was like, 'you're doing this.'"
Hannah Cox
