Hogwarts: Triwizard Cup

The cup represents a pivotal moment in the Harry Potter series. It was the port key that led to the death of Cedric Diggory and the resurrection of The Dark Lord. The cup is a great icon in the history of the wizarding world. It represented which school was the best in each 5 year period. 

In Harry Potter and the Goblet of Fire, Harry fought for his life to win the Triwizard Cup for Hogwarts. Barty Crouch Jr. made the cup a port key that transported Harry and Cedric to the grave of Lord Voldemort's father. It was here where Harry fights Voldemort  for the fist time and sees a glimpse of his parents.

The Triwizard Cup almost led to the death of Harry but in the end it saved his life when it sent him back to the safety of Hogwarts. Because of this vital scene, the cup represents the shift from the innocence of a young boy to the serious person he has to become to defeat the person who murdered his parents.