"You know there’s some interesting stuff in here... there are mountain trolls riding graphorns through Hungary, there are giants with winged tattoos on their backs walking through the Greek Seas, and the werewolves have gone entirely underground...."
-- Hermione Granger (CC1.5)
These are later reported at a public meeting held at the Ministry of Magic (CC1.12).
From the Web
Pottermore: Harry Potter and the Cursed Child
The theatre production opened in the West End of London at the Palace Theatre on 31 July 2016: Harry Potter and the Cursed Child, Parts One and Two