Sahih Bukhari Volume 2, Book 25, Hadith 1649

حَدَّثَنَا أَحْمَدُ بْنُ مُحَمَّدٍ، أَخْبَرَنَا عَبْدُ اللَّهِ، أَخْبَرَنَا عَاصِمٌ، قَالَ قُلْتُ لأَنَسِ بْنِ مَالِكٍ ـ رضى الله عنه ـ أَكُنْتُمْ تَكْرَهُونَ السَّعْىَ بَيْنَ الصَّفَا وَالْمَرْوَةِ قَالَ نَعَمْ‏.‏ لأَنَّهَا كَانَتْ مِنْ شَعَائِرِ الْجَاهِلِيَّةِ، حَتَّى أَنْزَلَ اللَّهُ ‏{‏إِنَّ الصَّفَا وَالْمَرْوَةَ مِنْ شَعَائِرِ اللَّهِ فَمَنْ حَجَّ الْبَيْتَ أَوِ اعْتَمَرَ فَلاَ جُنَاحَ عَلَيْهِ أَنْ يَطَّوَّفَ بِهِمَا‏}‏‏

Narrated By 'Asim : I asked Anas bin Malik: "Did you use to dislike to perform Tawaf between Safa and Marwa?" He said, "Yes, as it was of the ceremonies of the days of the Pre-Islamic period of ignorance, till Allah revealed: 'Verily! (The two mountains) As-Safa and Al-Marwa are among the symbols of Allah. It is therefore no sin for him who performs the pilgrimage to the Ka'ba, or performs 'Umra, to perform Tawaf between them.'" (2.158)