King Triton's trident is one of the most powerful objects in Auradon. It is now located in The Museum of Cultural History. This is proven true in Descendants: Wicked World because it was seen there in the episode, Steal Away. The Trident is only taken out for the mer-festival.
In Rise of the Isle of the Lost: A Descendants Novel, the Trident played a big role in the story.
This is one of two artifacts occasionally removed from the Museum of Cultural History for ceremonial use.