I think this is a bit of an upside-down view
. Until the 20th century, there was no such difference between a Christian pilgrimage to Santiago, Rome or Jerusalem. Pilgrims travelled any way they could - or could afford: on foot, on horseback, by boat, alone, in a group, with the staff of their household. And centuries later by coach, train, bus, car. While Rome and Jerusalem kept their attraction as a pilgrimage destination, Santiago lost its third place in the list. Lourdes, Fatima, and other Marian destinations rose. But still today, groups from mainly Spanish parishes travel as pilgrims by bus to Santiago, just as pilgrims travel by bus to Rome.
The uniqueness of the "
Camino de Santiago", ie walking it, is the fact that it was pushed and promoted for economic and political reasons in a form that just did not and does not exist for a way to Rome or to Jerusalem, and initially this promotion was not even aimed at walkers in the first place, and that secondly, several decades ago, Don Elías Valina and volunteer associations laid the foundations for the attractive infrastructure for walkers that we know today.