Elizondo to Isaba: the Basque Pyrenees at their wildest

Somewhere above Elizondo, the gravel narrows, the trees thin out, and the ridge opens into something closer to moorland than forest. There’s no fence, no sign, nothing marking a transition — just the surface changing underfoot and the view suddenly running in every direction at once. Off to the north, past the next fold of hills, is France. You can see the shape of it. You don’t ride into it.

That’s the character of the whole stage: proximity without crossing. On day three of the Trans Pyrenees Gravel route, our Pyrenees cycling tour from the Atlantic to the Mediterranean, you climb close enough to another country to feel the pull of it, and then the road bends back south, and Spain is where you stay — all week, start to finish.

Where this stage sits in the crossing

The Trans Pyrenees Gravel tour runs the full length of the range, San Sebastián on the Atlantic to Sant Pere Pescador on the Mediterranean — 780 km over eight riding stages and ten nights, with 17,000 to 20,000 m of cumulative climbing. It’s our longest and hardest route, run as a single Adventure-level tour rather than the two-pace split we offer elsewhere: everyone rides the same demanding line, guided or self-guided. The whole crossing is deliberately Spanish — San Sebastián, Elizondo, Isaba, Jaca, Aínsa, all the way to the Mediterranean coast at Sant Pere Pescador. That’s the route we designed, not a compromise.

This stage is the second day of riding, Elizondo to Isaba — 90 km and 2,600 m of climbing. It follows the opening stage out of San Sebastián, which takes you from the seafront through the Basque hills to Elizondo, a stone-built town in the green Baztan valley. From there the route climbs harder, holds altitude longer, and for a stretch of high ridgeline, runs along ground close enough to the frontier that the terrain itself starts to feel like border country — without ever crossing into it.

The Basque Pyrenees at their wildest

The numbers tell you it’s a serious stage: 90 km, 2,600 m of climbing, second day of an eleven-day trip. What they don’t tell you is the character of it. This is the Basque country showing its full hand — steep, wooded ramps low down, giving way to long gravel ridgelines above 1,000 m where the trees fall away and the views open in every direction. The road surface is honest rather than smooth: packed earth and stone that turns greasy quickly if the weather has been wet, which in this corner of the Pyrenees it often has.

This high country has been pasture to Basque and Navarrese shepherds for centuries — flocks moved between summer and winter ground along tracks much like the one you’re riding, long before anyone thought to ride a bicycle up here for pleasure. You feel that history in the shape of the land more than in any single landmark: worn paths that predate the road, stone shelters tucked into folds of hillside, a sense that this terrain has always been worked rather than simply admired.

The high, open section is also where the stage runs nearest the frontier — not a single dramatic moment so much as a sustained stretch where the ridge itself seems to mark a kind of edge, even while the road stays on the Spanish side of it throughout. Then the line bends back south, the descent into Isaba begins, and the country starts to feel settled again. Guides and riders who’ve done this stage more than once tend to agree it produces some of the best descents and views of the whole route, precisely because the terrain that makes for dramatic, high ridgeline riding also makes for interesting country to look at.

Isaba itself, where the stage ends, sits in the Roncal valley — a proper mountain village, tucked hard against higher ground, a fitting place to arrive after a day spent working for every kilometre.

Riding it well

A few things that make a genuine difference on a stage like this:

• Trust the GPS on the ridgeline, not your instinct. Above 1,000 m, junctions can be subtle and the correct line isn’t always the obvious one. This is exactly the terrain where the guided option’s local knowledge earns its keep, and where self-guided riders should keep the route file close rather than freelancing.
• Fuel before the climbing starts, not during it. 2,600 m over 90 km is a genuinely demanding profile from early on — this isn’t a day to run on empty legs and hope the scenery carries you through.
• Dress for altitude, not for the valley you started in. The high ridgeline sections catch wind and lose warmth quickly even when Elizondo felt mild at breakfast. A packable layer in a jersey pocket costs nothing and solves a real problem.
• Take a moment at the top. It’s easy to keep riding through open country that doesn’t announce its best viewpoint. Worth the ten seconds to actually look north, toward the hills that mark the frontier, before dropping back south.

Tyres and surface

Our minimum across every tour is 38 mm, wider is better, and on the Basque stages specifically we’d lean toward the wider end of that range set up tubeless. The gravel here mixes packed earth, loose stone and the occasional root-crossed section in the wooded lower slopes, and it drains unevenly after rain — a narrower, harder tyre gets caught out where a wider, softer-run one floats through. Our guide to gravel bike tyres for touring goes into the trade-offs if you’re deciding what to bring.

Isaba, and what comes after

From Isaba the route turns south and east, deeper into Spain. Stage four runs Isaba to Jaca — 85 km, 2,095 m, more descent than ascent but still real work, rolling mountain roads and forest gravel through country that starts to feel drier and more open. From Jaca the terrain changes character again: the route enters Zona Zero near Aínsa, one of Spain’s best-known gravel regions, before the rest day and the hardest stage of the entire crossing on the far side of it.

If you want the whole traverse laid out day by day — the Basque opening, the high central Pyrenees, the run down to the Mediterranean at Sant Pere Pescador — our full route guide, San Sebastián to Sant Pere Pescador: crossing the Pyrenees by gravel bike, covers it stage by stage.

What a supported Trans Pyrenees week includes

Ten nights in hotels and mountain refuges chosen for location, ten breakfasts and four dinners including the closing dinner on the Bay of Roses, and eight riding stages plus an optional rest-day ride in Aínsa. Whichever way you ride — guided, with an experienced English-speaking guide leading each stage and handling the navigation, or self-guided on the full GPS route for Garmin, Wahoo and Komoot — the support is identical: a support vehicle carrying spares, a spare bike and a clothing bag, luggage moved hotel to hotel so you collect your bag on arrival, a daily evening briefing with maps and elevation profiles, and the van meeting the group most days at lunch with a free refill of PurePower energy drink. Mechanic help comes from the crew, with parts at cost.

Guided groups run eight to ten riders per guide — smaller than most of our other tours, which matters on ridgelines like the one above Elizondo where good navigation and steady pacing count for more than usual. The full logistics, the 2027 and 2028 departure dates, and what’s included in full are on the Trans Pyrenees Gravel tour page; how our tours work explains the guided/self-guided model in more detail, and our levels page sets out how we grade the riding across the whole programme.

Why this stage stays with people

Most mountain stages are memorable for a single thing — a pass, a view, a climb with a name. This one is memorable for a feeling: a long stretch of open ridge where you’re riding closer to another country than you’ll be all week, near enough to see the shape of it, and the route simply doesn’t take you there. You climb into genuinely wild, remote country without ever leaving Spain, and somewhere in the 2,600 m between Elizondo and Isaba you understand a little better why this stretch of the Pyrenees has always felt like edge country — not because of a line on a map, but because of what the land itself does at altitude.

We ride this stage every September on the Trans Pyrenees Gravel crossing — guided or self-guided, San Sebastián to Sant Pere Pescador, with the support van somewhere below you on the valley road.