Arc of Attrition by UTMB
Arc 50
Porthcurno (Minack Theatre) → Porthtowan
Race guide
Updated 19 July 2026
The Arc 50 is the shorter sibling of the legendary Arc of Attrition 100, sending runners along one of the most demanding and dramatic stretches of the South West Coast Path. Starting beneath the clifftop Minack Theatre at Porthcurno, the race traces 81 km of the Cornish coastline north to the finish at Porthtowan — passing Land's End, Cape Cornwall and the boulder-strewn cliffs above Zennor before the course opens out onto the sandy bays approaching Hayle and Godrevy. Don't be deceived by the modest 1358 m of total ascent and a high point of just 114 m: the Arc 50 is defined not by big mountain climbs but by relentlessly technical, undulating coastal path where every metre of height is earned and lost again within a few hundred metres, and where the Cornish weather can turn the ground underfoot from firm to treacherous within minutes.
Course & Terrain
The race divides naturally into two very different halves. The first 36 km from Porthcurno to Zennor is among the most technical coastal running in the UK: narrow, rocky singletrack perched above Atlantic cliffs, with steep scrambling descents into coves and equally sharp pulls back out. The path through Cape Cornwall (17.5 km) and Pendeen (23.5 km) is particularly uneven, with exposed rock slabs, loose boulders and frequent stiles slowing progress to a walk for most runners. After Zennor the character shifts: the path to Lelant (51.3 km) and Hayle (54.7 km) eases considerably, and from Hayle the route rounds the Hayle estuary before tracking the broad dune-backed beach toward Godrevy (61.9 km). The final stretch from Godrevy through Portreath (73.7 km) to Porthtowan (80.9 km) returns to clifftop trail — still undulating but generally more runnable than the opening section, giving legs a chance to open up if they have anything left.
The Decisive Section: Porthcurno to Zennor
The race is almost certainly lost — though rarely won — in the first 36 km. The technical ground between Porthcurno and Zennor demands full concentration at all times: a rolled ankle or a stumble on wet rock early on can end your day. The cut-offs reflect this difficulty: you have until 16:40 to reach Zennor at 35.8 km, which sounds generous until you factor in darkness, wind and the sheer awkwardness of the terrain after Cape Cornwall. Runners who charge this section too hard arrive at Zennor with wrecked quads and empty glycogen stores, then face a still-substantial 45 km to the finish. The smarter approach is to treat everything from Pendeen to Zennor as a controlled effort — hike the steepest climbs, pick your footing carefully on the descents, and arrive at Lelant's drop bag station (51.3 km) with legs still under you.
Pacing Strategy
Because the Arc 50 is a point-to-point with a cut-off structure spanning into the early hours, pacing is about protecting the back half rather than banking time early. The Portreath cut-off at midnight (00:00) and the finish cut-off at 01:30 give a clear picture of the expected finishing window for mid-pack runners — plan on being on the trail for 14–17 hours. Use the easier middle section between Hayle and Godrevy to recover and move efficiently, resisting the temptation to hammer the flat estuary paths when your body wants to. The final leg from Godrevy to Porthtowan covers 19 km including the return to clifftop terrain, and many runners are navigating this section in full darkness; a conservative but steady effort here is more reliable than trying to make up time.
Fuelling & Aid Stations
With a drop bag available at Lelant (51.3 km), the race splits neatly into a 51 km first leg and a 30 km second leg for fuelling purposes. Front runners may reach Lelant in eight to nine hours; mid-pack runners closer to the 19:45 cut-off should plan to stop no longer than five minutes. Stock your drop bag for night running: a head torch top-up, dry gloves and a fast-absorbing carbohydrate source. Between the start and Lelant, aid stations at Land's End (7.5 km), Pendeen (23.5 km) and Zennor (35.8 km) are the key refuelling points — given the technical terrain, aim to consume 60–80 g of carbohydrate per hour rather than relying on big feeds at checkpoints. From Godrevy onward, the Portreath station at 73.7 km is your last opportunity to fuel and sort kit before the clifftop finish climb into Porthtowan.
Conditions to Expect
Cornwall's Atlantic-facing coast is notoriously exposed and the weather can change rapidly at any time of year. Wind is the constant: on the open cliffs between Cape Cornwall and Zennor, strong south-westerlies can make forward progress genuinely hard work and push wind chill well below the air temperature. Rain renders the rocky path sections extremely slippery; even in dry conditions, morning dew or coastal spray will keep the rock polished and treacherous. A waterproof jacket, gloves and a hat are not optional extras — they are kit-list essentials for this race. Because the Arc 50 runs into the night regardless of start time, runners should carry a primary and backup head torch from the gun; the clifftop sections after Godrevy have minimal light pollution and the path edge is unforgiving. Grippy trail shoes with a robust lug pattern are strongly recommended for the first half; maximal cushioning matters less here than ground feel and stability.
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Checkpoints & cut-offs
✓ Course data verified against the official source (2026-07-05) · official source
0 km · 26 m · —
7.5 km · 65 m · Sat 11:35
23.6 km · 67 m · Sat 14:20
51.2 km · 4 m · Sat 19:45
61.8 km · 6 m · Sat 21:40
73.6 km · 6 m · Sat 00:00
80.8 km · 100 m · —
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