The pallozas, archaic type of homes from which some specimens are preserved in the village of O Cebreiro, testify to a settlement before the Romans.

The Port of Piedradita was crossed by a Roman road that led from Astorga to Triacastela, on the interior the ancient Galicia.

The religious importance of this step was reinforced by the legendary miracle of the Holy Grail, which occurred in O Cebreiro, and since then a must for the Jacobean pilgrims.

In 1486 the Catholic Monarchs, on a pilgrimage to Santiago, stopped at the monastery of O Cebreiro and donated the shrine where the relics of the miracle.

The road also had great importance in the Spanish War of Independence, due to its strategic position between León and Galicia.