I visited this WHS in August 2014. The inscribed sanctuary in Tenoes is just a short detour from Braga. It was fun to catch a short funicular uphill ride to the sanctuary from the upper town of Braga, parallel to the Escadaria de Bom Jesus to the highest point of 116 metres at the statue of Saint Longinus.
The architecture of the zigzag baroque staircase is the main highlight of this WHS but it isn't unique in Portugal or on a global scale. Similar examples include the Sanctuary of Our Lady of Remédios in Lamego, the Nossa Senhora da Paz church in Sao Miguel, Azores or the Nossa Senhora dos Remedios Church in Sao Luis, Brazil and the inscribed Sanctuary of Bom Jesus de Matozinhos in Congonhas, Brazil. So its OUV lies in possibly being the first example of such an architecture which influenced the construction of other worldwide.
Being a pilgrimage site, as the pilgrims climbed the stairs, by tradition encouraged to do so on their knees, they encountered a theological programme that contrasted the senses of the material world with the virtues of the spirit, at the same time as they experienced the scenes of the Passion of Christ. The culmination of the effort was the temple of God, the church on the top of the hill. The presence of several fountains along the stairways give the idea of purification of the faithful. The 'new' church on top was one of the first Neoclassic churches of Portugal.