Sayyiduna Abu al-Darda' (may Allah be pleased with him) narrates: The Prophet (peace and blessings be upon him) said: "One prayer offered in al-Masjid al-Haram is equal to one hundred thousand prayers, one prayer offered in this mosque of mine is equal to a thousand prayers, and one prayer offered in Bayt al-Maqdis is equal to five hundred prayers."
Imam al-Tabarani recorded this in al-Mu'jam al-Kabir. Its narrators are thiqat (trustworthy), though some of them have been criticised, and this hadith is hasan (good).
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب الحج / 5873