Triathlon X - swimmers in the beautiful Ullswater © Steve Ashworth

Iron-distance races: the 11 toughest?

Make no mistake all 11 of these Ironman distance triathlons are tough and not for the faint-hearted, but which is the toughest long-distance race of all? We crunch some stats to find out...

01) TriathlonX, Ambleside, Cumbria: Tough score 89%

And the winner is... TriathlonX in the Lake District. A bike route on the legendary Fred Whitton cyclosportive route and a run up Scafell Pike and down again makes the new-entry TriathlonX the world’s toughest 226km triathlon.

“The bike is based on the infamous Fred Whitton cyclosportive route, the hilly granddaddy of all classic bike rides that happens to be 180km long. So it’s been an obvious long-held dream to have it as the showpiece of an iron-distance race," said Anthony Gerundini, 10th 2016 and 120+ time Iron finisher.

"The route takes in the iconic passes of the Lake District, including Wrynose and Hardknott, the cherry on this hilly cake. And it further spices up the route to include ‘The Struggle’ at Kirkstone Pass, familiar to anyone who’s done Helvellyn Tri, and the tough 25% gradient of the Honister Pass. The run then takes in the ascents through Mickelden, Rossett Ghyll and Esk Hause before the rock fields of Great End and Broad Crag. And then the challenge of England’s highest mountain, Scafell Pike, and back down again.”


Like this? Check out

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You've missed Swissman,

Arguably harder than Norseman at the least.


There's probably a typo for the Lanza swim temp. 29C is far from reality! Maybe 19C at best.


Don't forget the new one on the other side of the pond, Project DM


Take a look at /

That's a new tough one.


Agree wietcth TuckandGo with Swissman. And what about Altriman, Stonemanx Xtri (ambleside).... etc

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