حَدَّثَنَا مُوسَى، حَدَّثَنَا جَرِيرٌ، حَدَّثَنَا أَبُو رَجَاءٍ، عَنْ سَمُرَةَ، قَالَ النَّبِيُّ صلى الله عليه وسلم رَأَيْتُ اللَّيْلَةَ رَجُلَيْنِ أَتَيَانِي فَصَعِدَا بِي الشَّجَرَةَ، فَأَدْخَلاَنِي دَارًا هِيَ أَحْسَنُ وَأَفْضَلُ، لَمْ أَرَ قَطُّ أَحْسَنَ مِنْهَا قَالاَ أَمَّا هَذِهِ الدَّارُ فَدَارُ الشُّهَدَاءِ "
Narrated Samura:
The Prophet (ﷺ) said, "Last night two men came to me (in a dream) and made me ascend a tree and then admitted me into a better and superior house, better of which I have never seen. One of them said, 'This house is the house of martyrs."
Reference: Sahih al-Bukhari 2791
In-book : Book 56, Hadith 9
USC-MSA web (English) : Vol. 4, Book 52, Hadith 49 (deprecated)