Gothic in structure, Rococo in decoration, with portals to the dead located in the church's cellar.

The church of São Francisco's Gothic exterior reflects the modest, earthy mentality of the Franciscan order, while the extreme wealth of the patrons influenced the interior's gilded stylings. Below the church's three interior chapels, catacombs hold tombs for members of the Franciscan order as they await judgment day. Discreetly tucked in a corner of the crypt, in front of an hellish door to nowhere lies a glass, grated window in the floor allowing visitors to view the piles of human bones below their feet.

Such contrasts between earthy abundance and eternal austerity abound, including creaking floorboards numbering the dead's tombs beneath one's feet juxtaposed with an estimated 400kg of gold covering the ornate wood carvings and statues just one level above.

A somewhat hilarious/tragic (depending) historical side note:
Befitting his reputation for ridiculousness, when Napoleon conquered Oporto, he reportedly used the church, in all its opulence, as a stable for his horses.