At least some content in this article is derived from information featured in Fantastic Beasts and Where to Find Them (film). As such, spoilers will be present within the article.
This castle houses Ilvermorny School of Witchcraft and Wizardry. It stands at the highest peak of Mount Greylock, where it is concealed from non-magic gaze by a variety of powerful enchantments, which sometimes manifest in a wreath of misty cloud.
The castle was once a granite stone house constructed by Isolt Sayre and James Steward to be their home. When it eventually became a school, the cottage kept expanding until it became a castle.
The granite castle has marble statues of the founders Isolt Sayre and James Steward that flank the front doors of the castle. Inside, there is an Entrance hall, a circular room, with four large wooden statues of the four houses: Thunderbird, Horned Serpent, Wampus and Pukwudgie. There is a circular balcony where the older students watch in silence as the new students are sorted and is topped by a glass cupola. The Entrance hall has the Gordian Knot on the floor. There is also a large hall where students select or are selected by a wand. There are also dormitories and a tower with a stained-glass window with the Snakewood tree on it. On the grounds, the Snakewood tree still stands that grew from the buried wand and Isolt Sayre's tomb is also on the grounds with mayflowers placed at the tomb every year on the anniversary of her death. The Entrance Gates has the Gordian Knot on it.