At a time when Bragança was not yet called that, there was already the castle of Bemquerença, where a beautiful orphan princess, her niece lived with the lord of that castle.
The princess fell in love with a noble and brave knight who also liked her very much. This knight, however, belonged to a poor family and knew that under such conditions he could not aspire to marry the princess; so he decided to leave in search of fortune in other places, promising to return only when he felt worthy of being able to ask his uncle to marry him.
Years passed with the princess waiting for her knight and refusing all the marriage proposals that appeared to her.
Fed up with this situation, his uncle decided to marry her with a nobleman, his friend and very rich.
When the uncle presented his suitor to the niece, she immediately told him that her heart belonged to another who was to return one day, which left the uncle and his friend furious.
But soon her uncle thought of a solution to make her marry, and for the night he disguised herself as a ghost and entered her niece’s apartment by one of the two doors, frightening her and telling her that if she did not marry her uncle’s friend, she would suffer enormous misfortunes and torments all her life.
The princess, naturally terrified, was about to promise the ghost that she would marry her uncle’s friend when the other door to the room opened.
Through the door, although it was night, a ray of sun came in which illuminated the false phantom and denounced the lie of the princess’s uncle.
From then on the princess was never forced to break her promise and went to live in the tower ,that was forever remembered as the Princess Tower and those two doors became known by the Gate of Betrayal and the Gate of the Sun.