Of all the through hikes I wish I could do, the Camino de Santiago has been the highlighted one.
The Camino de Santiago (the way of St. James) is a route about 500 miles through the mountains of Northern Spain (there is a small part in France) to the Santiago de Compostela Cathedral, which is thought to be the final resting place for St. James.
The trip takes at least a month.
Fortunately, Spain has another trek called the Camino dos Faros (the lighthouse way). This trek walks along Spain's "Costa da Morte" and takes about eight days. The reports that I have read call the hike absolutely breathtaking.
It is also much less crowded than Santiago.
Where do you want to go?