(Al-Haaqa) 69 : 15
فَيَوْمَئِذٍ وَقَعَتِ الْوَاقِعَةُ
Then on that Day the Inevitable Event will happen.
The names of Surah 56 ‘Inevitable Event’, Surah 69 ‘The True Event’, and Surah 101 ‘The Horrible Event’ refer the Dooms Day and the events that will happen succeeding it. See explanation 1: 3.