Sahih Muslim Book 7, Hadith Number 2893.

Chapter : Excellence of walking at a quick pace in Tawaf and Umra and on the occasion of first Tawaf in Hajj.

Nafi’ reported on the authority of Ibn Umar (Allah be pleased with them) that when Allah’s Messenger (may peace be upon him) circumambulated the House, while observing the first circumambulation, he walked swiftly in three (circuits), and walked in four circuits, and ran in the bottom of the valley as he moved between al-Safa and al-Marwa. Ibn ‘Umar (Allah be pleased with them) also used to do like this.