Skellig Michael:

The line begins in Ireland, on a desert island, where Archangel Michael would have appeared to Saint Patrick, to help him liberate that country from the devil.

Here stands the first monastery of the line, that of Skellig Michael, Michael’s Rock. Fans of the latest Star Wars installments will recognize this site.
The line then heads south and stops in England on St. Michael’s Mount, a Cornish islet which, at low tide, joins the mainland. Here, St. Michael is said to have spoken to a group of fishermen.

Mont Saint Michel

The sacred line then goes on to France, on another famous island, in Mont Saint-Michel, also one of the places in which St. Michael has appeared.
The beauty of this sanctuary and the bay in which it is located, off the coast of Normandy, makes it one of the most visited tourist sites in all of France, and it has been a UNESCO World Heritage Site since 1979. Since the times of the Gauls, this place has been considered mystical.
In 709, the Archangel appeared to Saint Aubert, urging him to build a church in the rock. The works began immediately, but the Benedictine abbey was not fully built until the year 900.
Sacra Di San Michele

About 1000 kilometers away, in Val de Susa, the fourth sanctuary arises: the Sacra di San Michele. The very same straight line links this sacred place to the rest of the monasteries dedicated to Saint Michael.
The construction of the abbey began around the year 1000 and, throughout the centuries, new structures have been added to the original building. The Benedictine monks also added an inn, because this holy place was on the way of the pilgrims that traveled through the Via Francigena.

Santuario Di San Michele Archangelo

Moving another thousand kilometers in a straight line, one reaches Puglia, where an inaccessible cavern has become a sacred place: the Sanctuary of Saint Michael. Its story goes back to the year 490, when St. Michael appeared to San Lorenzo Maiorano.

Symi’s Monastery

From Italy, the archangel’s footprints reach the sixth sanctuary. This one is in Greece, on the island of Symi. This monastery houses a three-meter-high statue of the Archangel, one of the largest in the world.

Mount Carmel Monastery

The Sacred Line ends in Israel, at Mount Carmel Monastery, in Haifa. This place has been revered since antiquity, and its construction as a Christian and Catholic sanctuary dates back to the 12th century.