Urwa ibn al-Zubayr عروة بن الزبير · The Book on the Description of Hellfire

'Indeed the disbeliever's tongue will be stretched a Farsakh or two Farsakh, such that the people will walk upon it."

Kal Muhl, the Prophet (s.a.w)said: 'Like boiling oil, such that when it is brought close to his face, the skin of his face will fall off into it."

Have the Taqwa of Allah as His due, and do not die except as Muslims. And the Messenger of Allah (s.a.w) said: "If only a drop of Az-Zaqqum were to drip into the abode of the world, it would spoil the peoples' livelihood, so how about the person for whom it is his food?"

"And therein they will grimace in displace lips. -He will be grilled by the Fire until his upper lip is folded up reaching the middle of his head, And his bottom lip pains down, until it hits his navel."

"This Fire of yours, which the sons of Adam kindle, is one part from seventy parts of the heat of the Hell." They said: "By Allah! Would it not have been enough O Messenger of Allah?!" He said: "It is sixty-nine parts more – all of them similar in heat.” (Sahih)