In 1245 King Afonso III’s army surrounded Fernão Rodrigues, keeper of Celorico’s castle. Celorico da Beira had remained faithful to the deposed King Sancho II who at the time was in Toledo.

While his loyal and hungry men fought to defend the castle an eagle carrying a trout from the nearby Mondego River flew over them and dropped it. This event triggered the castle keeper to cook the trout very carefully. He then sent it as a present to the enemy accompanied by a message stating that he would continue to defend the castle for not only had he good horsemen but plenty of food supplies as well. The cooked trout was not only a present but also meant to prove his statement.

His enemies thinking that the trout was but a small sample of what existed within the castle decided to end the siege. They though that they would win by starving their enemies.