When to run on the Karst — why January

Walk or run on the Karst in high summer, through the lush Mediterranean scrub, and you often don’t realise how close the Karst escarpment is to the sea. A gennaio è tutta un’altra storia: the trees are bare, the low vegetation retreats, and from many stretches of the trail the Gulf of Trieste suddenly opens up, the white cliffs, and on the clearest days even Istria and the snow-covered Julian Alps on the horizon. It is the same view that opens up on the ridge sections of Monte Ermada, along the S1 Half Trail, where the bora blows freely and the view sweeps from the Julian Alps to Istria.

Why January is when you run the Karst

The Trieste Karst is a limestone plateau largely covered by mixed coppice woodland (downy oak, hop hornbeam, manna ash) and by karst heath, with Mediterranean scrub in the more sheltered dolines. From spring to autumn this vegetation is in full leaf: it encloses the trails in a green corridor and hides most of the views over the sea and the valleys, which open up only at the most exposed spots (escarpments, quarries, clearings). In winter the picture flips: the deciduous trees drop their leaves, the low vegetation goes dormant, and the viewpoints — the isolated openings of summer — become the rule for long stretches of trail.

It’s the same reason the most photographed and most talked-about spots on La Corsa della Bora are exposed ridge sections: the escarpment above PortoPiccolo and the Falesie Bianche, the Sentiero Rilke between Sistiana and Duino, the Monte Ermada loop, the high stretch above the Costa dei Barbari. In summer you pass through these places inside a tunnel of vegetation; in January you pass through them guardandoli.

The Karst climate in winter

The other half of the answer is the climate. Winter on the Trieste Karst is relatively mild for the latitude, thanks to the influence of the Adriatic: daytime temperatures that often stay above freezing, plenty of sunny days, no lasting snow at the heights the race courses reach (they stay below 500 m). This is no Arctic expedition: it is a Mediterranean winter, and you can run in it.

The one thing that really changes the game is the Bora: the katabatic wind that gives the race its name blows mainly in this season (approfondimento sulla pagina dedicata) and, when it blows, it sweeps the air clear of dust and haze — which is why the ridge viewpoints are at their sharpest on bora days, not in spite of the wind but thanks to it. Race weekend, always in January, has historically split almost half and half between bora and sirocco (the damp wind from the south-east): there is no guarantee of bora every year, but the winter window is by nature the one most exposed to the phenomenon that makes the Karst air clearer.

What about the other seasons?

Spring and autumn on the Karst are pleasant — mild temperatures, blossom in spring, warm colours in autumn — but by then the vegetation has largely grown back over the paths, and the open views are limited to the most exposed spots. Summer is hot and muggy, with the Mediterranean scrub at its fullest: lovely on days spent by the sea, less so for the views up on the plateau, where the dense green closes most of them off again.

Nessuna di queste stagioni è “sbagliata” per camminare o correre sul Carso. Ma solo gennaio brings the three conditions together — bare vegetation, clear air (when the bora blows), a climate you can still run in — and they are what really open the landscape up to the eye. It is a narrow window, and La Corsa della Bora was born right inside it.

L’evento della finestra invernale: la Corsa della Bora

La Corsa della Bora si corre ogni anno a gennaio tra il Carso italiano e quello sloveno, con partenza e arrivo tra Trieste centro e PortoPiccolo (Sistiana). L’edizione 2027 si corre il 9-10 January 2027 ed è la 12ª edizione della manifestazione (11 edizioni già completate dal 2016 al 2026), con 70 nazioni rappresentate e circa 3,300 participants nell’edizione più recente.

Seven distances, each a different way through the same winter window:

From 4 to 116 km, seven ways to be racing in the same January window — from the family pace of the S1 Borin to the whole night of the S1 Bora Ultra. The full picture of entries, time barriers and ITRA/UTMB Index certification for each distance is on the page Official Data La Corsa della Bora 2027; per iscriversi, la pagina Registration.

Explore the area at this time of year

The open January views described above are right there along the course — and they are worth a visit outside the race too, in this same winter window:

• Duino and the Rilke Path — il tratto panoramico per eccellenza tra le falesie, con vista sul Golfo di Trieste
• Costa dei Barbari — il litorale selvaggio incuneato tra le falesie bianche del Carso
• The Bora, the wind that gives the race its name — perché il vento invernale rende l’aria del Carso così nitida
• Trail running in Trieste and the Karst — l’hub con tutti i sentieri della zona (Alta Via del Carso, Sentiero Rilke, Val Rosandra, Napoleonica, Sentiero della Salvia)