Age Line

The Age Line (incantation unknown) was an enchantment used to prevent people above or below a certain age from accessing a specific object or place. It cannot be fooled or bypassed, even by a powerful brew like the Ageing Potion as proven by Fred and George Weasley, Summers and S. Fawcett; subjects who were not at the preset age and attempted to breach the spell regardless were thrown backwards and sprouted long white beards, regardless of gender.

On 30 October, 1994, Headmaster Albus Dumbledore used this spell on the Goblet of Fire in the Great Hall of Hogwarts Castle to restrain underage students from placing their names within the goblet for the Triwizard Tournament; anyone under the age of seventeen was forbidden from entering. He then traced a thin golden line with a ten-foot diameter on the floor around the goblet to show how far out the enchantment reached. Fred and George Weasley of Gryffindor, Summers of Hufflepuff and S. Fawcett of Ravenclaw all used Ageing Potion to attempt to bypass this line, believing that it relied on physical age as opposed to calendar age, and were all proven wrong; they all ended up in the hospital wing with long, fine white beards, as witnessed by Dumbledore himself, who found the notion amusing.

Behind the scenes

 * In the book, the thin golden line is a regular line and is gauged into the floor of the Hall; in the film, however, the line appears to be a mark of the spell itself, shimmering and glowing with a strange yellowish light.

Appearances

 * Harry Potter and the Goblet of Fire
 * Harry Potter and the Goblet of Fire (film)
 * Harry Potter and the Goblet of Fire (video game)
 * LEGO Harry Potter: Years 1-4
 * Pottermore