One of Ireland's leading ultra-athletes received a hero's welcome after successfully completing a back-breaking 5,000km coast-to-coast bike-and-run trek across the US

Shane Finn crossed the finishing line in New York after a grueling 36-day challenge, which saw him criss-cross 12 states by foot and cycle only.

The 26-year-old, from Dingle, Co. Kerry, took on the punishing feat -- otherwise known as American Ultra -- in a bid to raise over $250,000 for sufferers of spina bifida and hydrocephalus.

The back-breaking effort, which began in San Francisco on March 29, saw Finn cycle 270km for three consecutive days, then run up to 60km a day for another three consecutive days -- repeating this pattern six times in total, with no rest days.

Less than two years ago Finn completed 24 marathons in 24 days, raising almost $150,000 for the same cause in the process.

But after crossing the finishing line in New York city finally in sight, he admitted his latest challenge -- some of which saw him tackle snow-capped mountains and deserts -- was by far the most demanding test he's experienced to date both mentally and physically.

As he celebrated with supporters and fans with a burger and a pint of Guinness in a New York bar, he said, “I've almost been to hell and back since March 29.  Sheer fatigue and the relentlessness of every day -- just getting up and getting going again, and by six or seven at night you're empty and have to recover and go again."

Like his previous challenges, philanthropist Finn was inspired to take up this latest challenge by his cousin Mary Evans, 37, who lives with spina bifida and hydrocephalus.

And elaborating on the reasons behind his ambition to raise $250,000 or Spina Bifida Hydrocephalus Ireland (SBHI), he added, “This will ensure that essential respite services for over 100 children, teens and adults can continue. This respite is the only break most people living with the conditions will get in a year and SBHI rely on fundraising in order to keep this going."

For further information, including details on how to donate to SBHI, check out www.shanefinn.com.

Here's a video made about Shane Finn before he began his trek:

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Shane Finn.