Mont-Iseran legend

It all began in the 17th century: the earliest maps showed Mont Iseran but didn’t include its altitude. It was impossible to know if it was a mountain range, a peak, or simply the pass that we know today.

From one map to the next, its name varied, its position moved, and its identity changed. Some cartographers placed it at the location of today’s Aiguille Pers, others at the site of the huge Aiguille Rouge, the Signal de l’Iseran, and even on the very same spot as the mountain pass.

Still relatively unknown, Alpine geography provided scope for the imagination.

A great many travel guides however, contained obvious clues:

🔹Mountaineers crossed through the pass
🔹Some crossed it on horseback
🔹There were no descriptions of a 4,000-metre pyramid overlooking the sector

These witness accounts should have been able to dispel the myth, but the cartographers’ reputation and the lack of precise terrain knowledge were enough to maintain the illusion.

18th century land maps kept the legend alive

At that time, Savoie belonged to the Kingdom of Sardinia. Sardinian cartographers made very detailed maps of the Alps in order to strengthen their territorial control and scientific credibility. Mont Iseran appeared on them very clearly.

Its presence in these official documents gave it undeniable legitimacy in the eyes of Europeans. It even appeared in the list of the highest Alpine summits, even overtaking the Eiger (Switzerland – 3,967 metres).

Mont Iseran never existed, but its legend remains. It’s a reminder that maps are manmade, sometimes imprecise and influenced by the beliefs and guesswork of their eras.

The Col de l’Iseran is known today as one of the highest road passes in Europe and still carries this astonishing story: that of a summit born out of confusion that became a certainty, and then disappeared, after 255 years of appearing on maps.