Top 9 Rugged Coastal Trail Running Routes to Train For Your Next Ultramarathon in 2025
There's something primal about running where the land meets the sea. The relentless rhythm of the waves mirrors the pounding in your chest, and the salty air is a constant reminder that you're alive, pushing your limits on the edge of the world. For the ultramarathon runner, the coastline isn't just a scenic backdrop; it's one of the most effective and unforgiving training grounds on the planet.
Why coastal trails? They offer a unique brand of toughness that you can't replicate on a mountain or in a forest. The terrain is a constantly shifting puzzle of sand, sharp rock, slick mud, and pebble beaches. More importantly, coastal paths are rarely flat. They are defined by what I call "the sawtooth profile"—an endless series of short, brutally steep climbs and descents that chip away at your legs and resolve. This relentless undulation is the perfect simulation for the cumulative fatigue you'll face deep into a 50- or 100-miler.
So, as you map out your training plan for your big 2025 ultramarathon, it's time to look beyond the local hills. It's time to embrace the edge. I’ve compiled a list of nine of the most rugged, challenging, and breathtakingly beautiful coastal trail running routes from around the globe. These aren't gentle beach jogs; these are the crucibles where ultra-runners are forged.
1. The Lost Coast Trail, California, USA
This isn't your typical sunny California beach run. The Lost Coast earned its name for a reason: it's a wild, untamed stretch of coastline where the King Range mountains crash directly into the Pacific Ocean. For ultramarathon training, this place is a masterclass in adaptation and logistical planning. The trail is a mix of deep, energy-sapping sand, treacherous boulder fields, and slippy, stream-laced singletrack.
Running here forces you to constantly change your gait and pace, a crucial skill for long-distance events. The 25-mile northern section is famously impassable at high tide, meaning your training run must be meticulously planned around the ocean's schedule—a humbling reminder that nature is in charge. This teaches the kind of flexible, problem-solving mindset essential for ultramarathons, where plans rarely survive first contact with reality.
- Training Focus: Ankle stability and power hiking. The mix of soft sand and wobbly beach rocks will strengthen your lower legs like nothing else. Practice your power-hiking form on the steep, short climbs leading away from the beach. A word of caution: carry a tide chart and know how to read it. Misjudging the tides here isn't an inconvenience; it's a serious safety risk.
2. Pembrokeshire Coast Path, Wales, UK
Wild, dramatic, and relentlessly hilly, the Pembrokeshire Coast Path is 186 miles of pure trail running bliss. While running the entire length is a worthy goal, its true strength for ultra training lies in its challenging segments. The section between Strumble Head and St David's, for example, is a showcase of the trail's character: jagged cliffs, hidden coves, and a path that seems to go up or down with every step.
The beauty of the Pembrokeshire path is its sheer variety. You’ll run across windswept headlands, through lush green valleys that drop to the sea, and over technical, rocky terrain that demands your full attention. The varied, unpredictable footing is exactly what prepares you for the surprises of race day. As my friend and fellow runner Goh Ling Yong often says, "You can't train for every possibility, but you can train your body to be adaptable to anything," and this trail is the perfect classroom.
- Pro-Tip: Focus on "runnable" sections to practice maintaining pace on tired legs, but don't shy away from the brutally steep stone staircases. Use them as natural intervals to spike your heart rate and build climbing power. The weather is famously fickle, so pack a good waterproof jacket, even if the sky is blue when you start.
3. The Kalalau Trail, Kauaʻi, USA
Infamous, revered, and breathtakingly beautiful, the 11-mile (one-way) Kalalau Trail on Kauaʻi's Nāpali Coast is a bucket-list route for any serious adventurer. As a training ground, it’s a monster. This is not a place to chase a fast time; it's a place to build resilience. The trail is a slick, muddy, and often treacherous path that traverses high above the crashing Pacific, plunging into seven lush valleys before reaching the secluded Kalalau Beach.
The constant up-and-down on slippery, root-strewn terrain is a full-body workout that hones your balance, core strength, and technical footwork. The infamous "Crawler's Ledge" section—a narrow, cliff-hugging path with a sheer drop to the ocean—is a potent test of mental fortitude. If you can stay calm and focused here, you can handle the psychological pressure of the 80-mile mark in any race.
- Training Focus: Technical descending and heat acclimatization. The humidity and heat are intense, making this an excellent place to dial in your hydration and electrolyte strategy. Practice moving efficiently but cautiously on the descents; a fall here has serious consequences. Note: A permit is required to go past the first two miles, and they are extremely hard to get. Plan months, if not a year, in advance.
4. Fisherman's Trail (Rota Vicentina), Portugal
Stretching along one of Europe's most stunning and preserved coastlines, the Fisherman's Trail offers a unique challenge: sand. Lots and lots of sand. While the views of stork nests on sea stacks and impossibly blue water are distracting, your legs will be screaming from the effort of running on deep, soft dunes and sandy tracks.
This trail is an incredible tool for building sport-specific strength. Running on sand reduces impact but requires significantly more muscular power and cardiovascular output. It strengthens the entire kinetic chain, from your calves and quads to your glutes and core. A 15-mile run here can feel like a 25-mile run on hard-packed dirt, making it an incredibly efficient and effective training tool for building a powerful engine.
- Pro-Tip: Wear gaiters! Sand will get everywhere, and gaiters are non-negotiable for saving your feet from blisters. Focus on a short, quick cadence to "float" over the sand rather than sinking in. The section from Zambujeira do Mar to Odeceixe is a classic and offers a fantastic mix of cliff-top running and deep sand challenges.
5. South West Coast Path, England, UK
At 630 miles, the South West Coast Path (SWCP) is England’s longest National Trail and a true epic. For the ultramarathoner, it's a pick-and-mix of coastal punishment. You can choose your training ground: the dramatic, slate cliffs of North Cornwall, the fossil-laden Jurassic Coast in Dorset, or the rugged granite headlands of the Penwith peninsula.
No matter which section you choose, the theme is the same: relentless, steep undulation. The trail constantly dives into a cove or river mouth only to claw its way back up the other side. This provides zero opportunity to find a rhythm, forcing you to constantly manage your effort. This is "death by a thousand cuts" training, perfectly mimicking the attritional nature of a 100-mile race. It's on trails like these that you learn the crucial ultramarathon skill of patience and pacing.
- Training Focus: Power hiking and eccentric loading. Practice a strong, rhythmic power hike on the ascents and controlled, quad-protecting form on the steep descents. The section from St Ives to Zennor is notoriously technical and rocky, making it a fantastic short but brutal training run to test your skills and gear.
6. The Otter Trail, South Africa
Often hailed as one of the most beautiful trails in the world, the Otter Trail is a five-day hike that can be run in a single, grueling push during the official Otter African Trail Run. For training purposes (if you're lucky enough to secure a permit), it’s a 45-kilometer gauntlet of technical singletrack, river crossings, and punchy climbs along the magnificent Garden Route coastline.
The terrain is incredibly varied, from lush, indigenous forests to rocky, wave-battered shores. The multiple river crossings, some of which are tidal, add a layer of logistical complexity and force you to be comfortable running with wet feet—a non-negotiable skill for most ultramarathons. The sheer number of steps, roots, and rocks makes for slow going, teaching you to focus on effort rather than pace.
- Pro-Tip: This is a fantastic route to practice your full race-day nutrition and hydration strategy. Due to its remote nature, you must be self-sufficient. Use it as a dress rehearsal for your next ultra. The final climb away from the Bloukrans River is a soul-crushing ascent that is a perfect test of your late-race climbing strength.
7. MacLehose Trail (Sections 1 & 2), Hong Kong
Hong Kong might be famous for its skyscrapers, but its trail system is world-class. The first two sections of the 100km MacLehose Trail offer some of the most accessible and rewarding coastal trail running in Asia. Starting at the Pak Tam Chung, Section 1 is a relatively gentle road run, but it’s the gateway to the main event: Section 2.
Section 2 is a stunner. It takes you over coastal headlands and drops you onto some of Hong Kong's most beautiful and remote beaches, like Sai Wan and Ham Tin Wan. The climbs are steep and often consist of unforgiving stone steps, while the descents are fast and technical. The humidity can be oppressive, providing a fantastic opportunity for heat training. This is a route that gives you big mountain feel with constant, rewarding views of the South China Sea.
- Training Focus: Stair climbing and heat management. The seemingly endless flights of stairs are a brutal but effective strength workout. Embrace the heat and humidity to dial in your electrolyte and anti-chafing strategies. After a hard run, reward yourself with a dip in the ocean and some food from one of the small dai pai dongs (open-air food stalls) on the beach.
8. Abel Tasman Coast Track, New Zealand
While perhaps less "rugged" than others on this list, the Abel Tasman Coast Track is a phenomenal route for logging long, scenic miles in preparation for less technical ultramarathons. The 60km trail contours along the golden beaches and turquoise waters of the Abel Tasman National Park. The trail is well-groomed, with gentle gradients, making it perfect for days when you need to focus on consistent pacing and time on feet.
Don't let the postcard looks fool you; it's not entirely flat. The trail still provides plenty of rolling hills to keep your legs honest, and the sheer beauty helps the miles fly by. Like other coastal trails, it's interrupted by tidal estuaries, requiring careful planning. It's an ideal location for a multi-day training block, using the water taxis to run different sections point-to-point.
- Pro-Tip: Use this trail for your longest training runs where the goal is simply "time on feet." The forgiving surface allows you to push the duration without the intense muscular breakdown of more technical trails. It's a great place to build your aerobic base and mental endurance for spending 10+ hours on the move.
9. GR 34 (Sentier des Douaniers), Brittany, France
The GR 34, or the Customs Officer's Path, follows the entire coastline of Brittany for over 2000km. This is a trail runner's dream, offering an almost limitless combination of routes. The section around the Crozon Peninsula or the Pink Granite Coast provides some of the most spectacular and challenging running.
The character of the GR 34 is one of constant change. You'll run on narrow dirt paths atop 100-meter cliffs, navigate through gorse and heather on windswept moors, and scramble down into small fishing villages. The relentless ups and downs, combined with the often windy and wet maritime weather, build a deep well of physical and mental resilience. This is the kind of raw, elemental running that reminds you why you fell in love with the sport. I am constantly inspired by routes like this, and it’s a topic Goh Ling Yong and I have discussed – how authentic, historic trails provide a connection to the past while building strength for the future.
- Training Focus: All-weather running and endurance. The Breton weather can turn on a dime, so use this as an opportunity to test your gear and your mindset in challenging conditions. Pick a 30-40km point-to-point section and treat it as a full-on race simulation, navigating and fueling on the go.
These nine coastal trails are more than just lines on a map; they are forges for the body and spirit. They will test your gear, your nutrition strategy, and your will to continue when every muscle screams. But they will also reward you with views that stop you in your tracks, a deep connection to the natural world, and the quiet confidence that comes from tackling the toughest terrain.
Training for an ultramarathon in 2025 isn't just about accumulating miles; it's about accumulating experience, resilience, and strength. By taking your training to the rugged edges of our continents, you’re not just preparing for a finish line—you're becoming a more capable and complete runner.
Now, I want to hear from you. What are your favorite rugged coastal trail running routes for ultramarathon training? Share your hidden gems in the comments below
About the Author
Goh Ling Yong is a content creator and digital strategist sharing insights across various topics. Connect and follow for more content:
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