Abbas bin Abdul-Muttalib reported,
We were sitting with the Messenger of Allah ﷺ at al-Batha when a cloud passed by. The Messenger of Allah ﷺ asked, "Do you know what this is?"We replied, "A cloud."He said, "And the rain cloud?"We said, "And the rain cloud."He said, "And the thick cloud?"We fell silent. Then he asked, "Do you know how far it is between the heaven and the earth?"We said, "Allah and His Messenger know best."He said, "Between them is a distance of five hundred years, and from each heaven to the next is a distance of five hundred years, and the thickness of each heaven is a distance of five hundred years. Above the seventh heaven is a sea, and the distance between its bottom and its top is like the distance between the heaven and the earth. Then above that are eight mountain goats, and the distance between their hooves and their knees is like the distance between the heaven and the earth. Then above that is the Throne, and the distance between its bottom and its top is like the distance between the heaven and the earth. And Allah 
is above that, and nothing of the deeds of the children of Adam is hidden from Him."
Ahmad 1770
Daifحدثنا عبد الرزاق أنبأنا يحيى بن العلاء عن عمه شعيب بن خالد حدثني سماك بن حرب عن عبد الله بن عميرة
عن عباس بن عبد المطلب قال
كنا جلوسا مع رسول الله ﷺ بالبطحاء فمرت سحابة فقال رسول الله ﷺ أتدرون ما هذا قال قلنا السحاب قال والمزن قلنا والمزن قال والعنان قال فسكتنا فقال هل تدرون كم بين السماء والأرض قال قلنا الله ورسوله أعلم قال بينهما مسيرة خمس مائة سنة ومن كل سماء إلى سماء مسيرة خمس مائة سنة وكثف كل سماء مسيرة خمس مائة سنة وفوق السماء السابعة بحر بين أسفله وأعلاه كما بين السماء والأرض ثم فوق ذلك ثمانية أوعال بين ركبهن وأظلافهن كما بين السماء والأرض ثم فوق ذلك العرش بين أسفله وأعلاه كما بين السماء والأرض والله تبارك وتعالى فوق ذلك وليس يخفى عليه من أعمال بني آدم شيء
Its chain is very daif indeed. Yahya bin Ala Razi Bajali, Bukhari said in al-Kabir 2/29/4, "Waki used to speak critically of him," and he said the same in al-Duafa 37. Nasai said in al-Duafa 31, "His hadith is to be abandoned." In al-Mizan and al-Tahdhib, Ahmad bin Hanbal said, "A liar who fabricates hadith." In al-Tahdhib, Waki said, "He used to lie. He narrated about twenty hadiths concerning the removal of the sandals."Abdullah bin Umayrah, Ibn Hibban mentioned him among the trustworthy narrators, and Tirmidhi graded his hadith hasan. He narrates in this chain from Abbas, and were it not for the weakness of the chain, his hadith would have been sahih, because he was ancient, having reached the pre-Islamic era, and he was the guide of al-Asha, as Abu Naeem said. For this reason, the Hafiz gave him a biographical entry in al-Isabah 5:94.It is well known that he narrates this hadith from Ahnaf bin Qays from Abbas, so Bukhari's statement, "It is not known that he heard from Ahnaf," does not invalidate his narration, since he was ancient, having reached the pre-Islamic era, and so he was a contemporary of the Messenger of Allah and the senior companions. This hadith, by this route, was narrated by Baghawi in his tafsir 465-466, with his chain going back to Abdul-Razzaq. Further discussion and sourcing will follow in the hadith after this one.Batha, this is Muhassab, a well known place in Makkah.Muzn, clouds and cloud cover.Anan, with a fatha on the ayn, means clouds. "Do you know," in K, it reads "Do you know" (variant form). "The thickness of each heaven," this is how the word was written in K. In H it was written "how," but in my view this is a mistake for which I can find no explanation. I can only read it as "kathf," with a kasra on the kaf and a fatha on the tha, on the pattern of "ghilaz" and with its meaning, but I could not find this pattern derived from the root k-th-f. Rather, they say "kathafa yakthufu kathafah," with damma on the tha in both the past and present tense, and fatha on the kaf in the noun form. What appears in Baghawi's version is "the thickness of each heaven," and likewise in some versions of the coming hadith.The word "distance" is an addition found in K.Awal is the plural of wal, with fatha or damma on the waw and kasra on the ayn, originally meaning mountain goat. What is meant here is angels in the form of mountain goats, as Ibn Athir said in al-Nihayah.