Ahmad said:
Husayn ibn Muhammad narrated to us; Khalaf ibn Khalifah narrated to us, from Yazid ibn Kaysan, from Abu Hazim, from Abu Hurayrah, who said:
“We were in the presence of the Messenger of Allah ﷺ one day when we heard a loud thud (1). The Prophet ﷺ asked, ‘Do you know what that was?’ We replied, ‘Allah and His Messenger know best.’ He said, ‘That was a stone that was hurled into Hell seventy autumns ago, and only now has it reached its bottom.’”
Muslim also transmitted it—from Muhammad ibn ʿAbbād and Ibn Abī ʿUmar, through Marwan, from Yazid ibn Kaysan—with a similar wording (2).

[Another narration]
Al-Ḥāfiẓ Abū Nuʿaym al-Iṣbahānī said: ʿAbd al-Malik ibn al-Ḥasan ibn Yūsuf al-Saqaṭī narrated to us; Ahmad ibn Yaḥyā narrated to us; Abū Ayyūb al-Anṣārī, Ahmad ibn ʿAbd al-Ṣamad, narrated to us; Ismāʿīl ibn Qays narrated to us, from Yaḥyā ibn Saʿīd, from Abū ʼl-Ḥubbāb Saʿīd ibn Yasār, from Abū Saʿīd al-Khuḍrī, who said:
“The Messenger of Allah ﷺ heard a sound that startled him. Jibrīl came to him, and he asked, ‘What is this sound, O Jibrīl?’ He replied, ‘It is a rock that fell from the rim of Hell seventy years ago; it has now reached its bottom, and Allah wished to let you hear its sound.’ After that day, the Messenger of Allah ﷺ was never seen laughing with a full mouth until Allah—exalted is He—took his soul (3).”
Al-Bayhaqī also related it, through Abū Muʿāwiyah, from al-Aʿmash, from Yazid al-Raqāshī, from Anas, from the Prophet ﷺ in a similar vein (4).

It is authentically recorded in Ṣaḥīḥ Muslim that ʿUtbah ibn Ghazwān said in a sermon: “We have been told that a stone is flung from the edge of Hell and plunges for seventy years without reaching the bottom. By Allah, it will surely be filled—are you astonished? And we have been told that the distance between the two leaves of one of the gates of Paradise is a journey of forty years, yet a day will come when it is jam-packed with crowds” (5).

[Another narration]
Al-Ḥāfiẓ Abū Yaʿlā said: ʿUthmān ibn Abī Shaybah narrated to us; Jarir narrated to us, from ʿAṭāʾ ibn al-Sāʾib, from Abū Bakr (6), from his father Abū Mūsā [al-Ashʿarī], who said: “The Messenger of Allah ﷺ said, ‘If a stone…’”