Sahih al-Bukhari 4413
Narrated Hisham's father:
In my presence, Usama was asked about the speed of the Prophet (ﷺ) during his Hajj. He replied, "It was 
Al-`Anaq (i.e. moderate easy speed) and if he encountered an open space, he used to increase his 
speed."
حَدَّثَنَا مُسَدَّدٌ، حَدَّثَنَا يَحْيَى، عَنْ هِشَامٍ، قَالَ حَدَّثَنِي أَبِي قَالَ، سُئِلَ أُسَامَةُ وَأَنَا شَاهِدٌ، عَنْ سَيْرِ النَّبِيِّ، صلى الله عليه وسلم فِي حَجَّتِهِ‏.‏ فَقَالَ الْعَنَقَ، فَإِذَا وَجَدَ فَجْوَةً نَصَّ‏.‏