Dom Luis Bridge over the Douro River in Porto (Portugal) painted by Julio Costa

Next to the Douro River lived long time ago a giant, always amused by playing dice. One night the giant dreamed that a man dressed in white, with a white beard, appeared to him and asked him to go down to the mouth of the river to build several churches there. "When you wake up take your dice throw them from the highest hill." Where the dice fall, churches must be built. The numbers on their faces will represent the number of blue and white tiles with which they will be decorated. So now, where they fell, are today the churches and monasteries of the city of Porto.

Legend of Porto