The UK’s best iron-distance triathlons

In the UK we are lucky to have a whole host of triathlons, from super sprints to iron distances, to choose from. Here we share some tips and advice for racing 7 of the UK's favourite full distance triathlons

Our top 7 Ironman-distance events in the UK

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Ironman UK

Where: Bolton, Manchester
When: July

It’s the original UK long-distance race, with colourful crowds and a famous finish line experience. But how do you conquer the logistics, lumpy bike and lapped run of Bolton? Janine Dogget, 2015 Ironman UK finisher (14:34:27) and 3:46hr Paris Marathon athlete, has this advice.


Lanzarote it isn’t, yet modest Bolton provides an incredible Ironman race. The locality and calm lake swim make it an ideal first-time choice, while the bike course will challenge the toughest of riders.

It’s a good idea to recce the course before, and Pennington Flash offers swimming every Saturday morning before the big day. On race day, getting to the start is easy, but leave time to find the nutrition and post-race bag drop area as this isn’t immediately obvious.

The swim

The race kicks off at 6am with a two-lap swim and, despite the quiet nervousness of over 2,000 people in neoprene, the well-organised start pens help to calm you before setting off.

The Flash is a decent temp (19°C in 2015) and there’s plenty of space to find your rhythm, but the water can be choppy. The buoys are easy to spot and the Aussie exit between laps is great for mentally breaking down the swim.

The bike

After a short run to T1, a two-lap course through beautiful Lancashire countryside awaits. With 1,641m of ascent, Sheep House Lane is a tough 3km star of the show. There’s a technical bit at the foot of the descent that can catch people out – it’s marked but stay on guard (and ideally on your bike!).

Some sections are spookily quiet, but there’s sensational sporadic support en route, with locals sporting some outrageous outfits! At the Macron Stadium and T2 (it’s a split transition) there’s no assistance in racking your bike so be ready to find your number. The T2 tent offers a slightly larger privacy screen than T1, so if you want fresh kit for the run you can strip off.

The run

There’s a 10km point-to-point route before the lapped 8km course, which makes it up to 42.2km. It’s mostly flat but the laps are mentally challenging and, as it’s in a built-up area, there aren’t many nice views. The aid stations every 4km offer bananas, sugary drinks and a bucket-load of cheers!

Having visited it three times already, the finisher funnel will feel like an old inflatable friend by the time you reach it. Ironman UK finishes at 11pm before it’s packed up fast, as if it were all just a beautiful dream of lactic acid, Lycra and ecstatic tears!

Ironman UK – course tips and everything you need to know


Where: Hever Castle, Edenbridge

When: July

This Kent-based 226km is the beauty and the beast of the UK Iron-distance circuit, with both luscious
rural scenery and lung-busting climbs. Anthony Gerundini, who finished ninth in 2015 with a time of 11:57:28 and finisher of more than 107 irons, explains how to battle the Bastion.


On arrival there’s a big signposted event car park. There’s a grassy path to walk on to get to registration and transition, which is fairly short but awkward to carry all your stuff over if you’ve no support with you.


The swim starts under the backdrop of an Italian-style loggia, a fantastically unique feature. It’s quite a long walk from transition so leave yourself more than enough time to get there if you want a warm-up. The start is relaxed, no aggro at all.

The lake is a bit murky but the sights en route (including a Japanese teahouse) and footbridges where crowds can gather to shout encouragement more than make up for this. There’s also a floating table with drinks at halfway, another unique and thoughtful touch from the organisers.


The bike is three 60km laps on a scenic but rewarding course. There are some short and steep climbs to get your teeth into, and also some long steady inclines, so don’t overcook these. Beware of the descent out of Fordcombe – it’s shaded and quite damp and caused an accident in 2014, but they’ve now put a marshal there with a huge red flag to remind you to slow down.

The course isn’t closed to traffic but it might as well be as there’s very little traffic anyway, and the comprehensive Stop/Go traffic management from the marshals is M-Dot standard. I’ve completed The Bastion numerous times and have never had to stop for traffic. The final stretch along the Chiddingstone Causeway is relatively flat to spin the legs out before the run. Just beware going under the narrow and twisty rail bridge, which is quite potholed.


The run is quite an adventure, comprising of four wide laps out into the countryside on a non-technical trail. On exiting the castle grounds, there’s a really short and steep hill, which is an ideal place to take a power-walking break and get some fuel in. You don’t see your rivals often as there aren’t many switchbacks, so you’re always on your toes knowing you could be caught at anytime.

You can lose so much time later on if you don’t pace it properly, so do the first couple of laps ‘feeling easy’, with the challenge being to replicate those times on the last two laps. It’s 6.5km between the first two feed stations so you might want to carry an extra gel. There are loads of marshals to keep you going in the right direction along the twists and turns, so you shouldn’t have any navigational issues.


Where: Ashton Keynes, Gloucestershire

When: July

Great for iron newbies and PB hunters, the 226 is a small but loved Iron circuit fixture. So how do you whup the west country wonder? 2015 finisher Mary Morton has this advice


There’s plenty of space at the venue and everything you need is close by. You don’t need to rack the day before, and registration is painless. Camping is available but there’s also plenty of accommodation nearby. Transition is clearly set out with loos and segregated changing yards from the bikes.


There’s a gentle slope into the crystal clear water, which is cool but definitely not cold. There’s also plenty of opportunity to warm up if you need to. It’s a two-lap swim course, which skirts around the outside of the lake with a short dogleg into the middle. Sighting is easy as there are big buoys and several landmarks. Spectators can also follow easily. Due to the calm and predictable waters, pacing is a doddle and the exit is via a ramp with helpful hands to guide you to your feet. The journey to T1 is a short one.


The bike is also two laps, and having recce’d the course I knew there were some gentle climbs in store despite it being reportedly flat. The first aid station is only about 16km in. The countryside is beautiful and the roads smooth. There are few technical turns and climbs, yet the exposed course can exacerbate spray if it’s raining. The support is thin so the sight of marshals is welcome.


T2 is stress-free, and there was plenty of toilet roll left in the portaloos by the time I arrived! The run is four laps, so it can be psychologically damaging if you see athletes already sporting bands when you start. But the aid stations are well-stocked and the organisers offered to supply anything we asked for.

We named the Cotswold 226 4th best Iron-distance tri for beginners in Europe


Where: Dartford, Kent

When: August

If battling 226km isn’t hard enough, the Midnight Man organisers throw a night event at you. Here’s how to race in the dark of Dartford by a man who knows, 2012 second placer Dave Clamp


Take kit for all temperatures: it can be hot in the evening, but that can change by 3am and you’ll feel it if you’re down to walking pace on the run. Doing the marathon at night can be pleasant, though, compared to suffering in the heat at many summer daytime Ironman races. For the race, it’s worth practising nutrition for the later start time and doing some sessions where you swim at 6pm, then go for a 3-4hr bike to acclimatise to cycling as it changes from day to night.


One factor is that you’ll be swimming when the sun is getting low, so sighting is difficult. Walk round the lake’s edge to spot landmarks to aid direction, as the early evening glare can make the buoys difficult to spot. Also make sure your crew take plenty of insect repellent; they’ll be sitting at dusk and dawn near still water. My daughter was so badly bitten that she was off work afterwards!


Cycling in the dark feels quite strange because you have the sensation of moving faster than you really are. So use a powerful front lamp and make sure that it’s very firmly fastened on; there are a few speed bumps on the course and mine came flying off a few times. There were a lot of punctures when I did it, so be prepared physically and mentally for that, and practise changing punctures before the race.


Like the bike, the marathon run course is fairly flat so fast times can be recorded here. But be prepared for bigger potential changes in temperature than on a normal daytime Ironman. You can get quite cold in the night, especially if you start walking.

We named the Midnight Man the 9th best Iron-distance tri for beginners in Europe



Where: Holme Pierrepont, Notts

When: July

We named this regular 220 Award-winner the most beginner friendly ironman-distance triathlon in Europe, despite the often not so friendly weather. Here’s 2015 finisher Jason Scott with some essential advice for your Nottinghamshire crusade…


I chose The Outlaw because I’d heard good things and it’s known for being considerably flatter than Ironman UK. I’d say if you’re not signed up for an M-Dot event then this is the next (or arguably should be first) on your list of must-do long-distance races.

Myself and a friend camped on site, only 200m from transition. They also offer luxury wooden pods to stay in, which I’d recommend for extra comfort. Registration is a breeze the day before, and set-up is quick and no hassle.


The Outlaw swim is a proper Iron start. None of this small pens of starters at a time; it’s a mass underwater wrestle! If you’ve positioned yourself correctly according to your predicted time, though, you should be fine; it soon thins out. It’s one large lap, which is right to the end of the rowing lake and back again.

If it’s a sunny early morning, sighting on the swim can be quite difficult as the sun is low.Unless you’re flying at the front, just do as I did and follow the few hundred people in front of you! The transition area is great, slick and easy to get through, and there are lots of great viewing spots around the lake for family and friends to cheer you on.


The bike course is a flat-ish 180km. It’s more rolling tarmac than anything else and a good average speed can be met quite easily. You get some nice views of the Nottinghamshire countryside, and the course is three laps (laps one and three are the same), making it easy to mentally divide up.

The feed stations are long, which make it easier to grab nutrition en route, and the support is excellent, even though the weather in 2015 was absolutely terrible!


The run is a flat and well-supported route, which starts off with a lap of the lake and then continues along the River Trent. This is done twice before a final loop of the lake to finish off.

Walking through the aid stations helped me immensely, and my general Iron race tip would be to never stop completely and keep walking through.

There are plenty of feed points en route so plenty of chances to recharge your batteries. The great marshals are particularly appreciated towards the end of the run course when, although you’ve had a long day, theirs has probably been even longer!


Where: Llanberis, Gwynedd, Wales

When: September

With its huge amount of climbing and 16:50hr median finish time, we named The Brutal the 2nd toughest Ironman-distance triathlon in the world. But fear ye not Brutal entrants, here are the winning tips for Snowdonia success from 2015 winner David Chapman …


This is one tough race. Snowdonia will probably involve a fair drive to get to, so get this done sooner rather than later. Racking your bike the night before can help reduce grief on race day, or turn up early to secure a place in the small car park right by transition. Book somewhere to stay in Llanberis itself, that way you’re never too far from the race headquarters.


Llyn (lake) Padarn is famously cold. A neoprene cap really helps with warmth, and you can even use neoprene socks and gloves.  We’ve kicked off with a hard frost on the ground in the past but, even if it’s warmer, a decent run between swim exit and transition means it’s a good idea to bring an extra pair of run shoes. Have a short warm-up before the deep-water start. It’s four triangle laps with an exit and re-entry after two, so don’t rush this too much.


The bike exits onto a fairly busy road. It’s brilliantly marshalled but stay alert. There’s a pedestrian crossing soon after, if you get a red relax and take in some calories. The 45km loop starts with the only flat section before tackling the first of many small climbs. The first real test is a short, steep climb after a left turn. Beware of clawing back time on the descent here; it’s on the narrow side, there are speed bumps and a sharp left at the bottom.

The other significant climb at 32km is 7km long but shallower, culminating in Pen-y-Pass. Again resist going flat out on the descent; stones, sheep, walkers and vehicles in the middle of the road are real dangers. When you start to struggle (and you will!) the stunning scenery can help ease the pain.


The tame surfaces lull you into a false sense of security early on the run. At the end of Lake Padarn the road turns uphill and stays that way for 2km. Going too hard here’s a mistake. It’s then almost all downhill to the aid station. This contains some tricky rolling trails, tree roots and loose rocks.

Once the three laps are complete, medics check you/your backpack and you head up Wales’ tallest mountain. Before long, the tarmac kicks up at an horrendous angle. This first Snowdon section is the hardest and, unless you’ve mountain running pedigree, power walking is your best bet. Make sure you check-in with the medic before the summit and cautiously enjoy the return. All but the fastest few will finish in the dark, so a powerful head torch is strongly recommended.



Where: Tenby, Pembrokeshire

When: September

With bumper support and plenty of beauty, Ironman Wales is a classic on the Ironman circuit. But facing down IM Wales ain’t for the faint-hearted and we rated it the 9th toughest Iron in the world.  Here are your ultimate tips from 2014 finisher and tri coach Mark Kleanthous.


In Tenby you have a 1km walk from transition to the swim start. If it’s cold and wet, wear your wetsuit to the start, otherwise put it on when you arrive. Allow enough time to get to the start and place your shoes and a drink in your allotted number spot on the zigzag stairs for the run to T1.


This is a scenic two-loop triangular swim. Keep left at the start to keep you out of the congestion during the rest of the swim. Use the giant rock that juts out in the bay, the lifeboat house, moored boats and the colourful houses overlooking the skyline to navigate. But be careful running in soft sand after the first loop. Jog instead of running as you still have plenty of running to come. Remove your wetsuit after exiting the swim before the long 1km stretch to T1.


Hold back for the first 30mins of the bike and start hydrating after 5-10mins with water, and then start your nutrition plan. I’d use a road over a TT bike to combat the 18-22% steep hills.

The steepness of the climbs makes Tenby one of the hardest 180km courses, which requires you to have suitable gears to spin up and save your strength for the marathon. I’d recommend those wanting to complete the ride to use a 34/28t chainset. Those with sub 6:45hr ambitions go for a 34/26t or 42/32t.

There are a few technical sections, especially ‘Heartbreak Hill’ at Saundersfoot. Drive this section before and mentally plan how you’ll tackle it in both the dry and wet. Don’t get sucked in by the crowds; hold back and ride within your ability.

The run course is demanding with the first 3km going straight uphill, which you have to complete four times. Because the hills are short and steep or long, the 42.2km demands that you keep mental control to hold back. The downhills require you to relax and keep your shoulders loose to reduce impact. Far too many triathletes, including experienced Ironman competitors, push too hard on the early hills and are forced to slow up. Success is only achieved by maintaining a constant effort. I’d wear a supportive run shoe to give you protection for the descents and cobbled parts.

We named Ironman Wales the 9th toughest Iron-distance triathlon in the world

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Read some more tips for racing Ironman Wales from Lucy Gossage and Scott Neyedli here

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