Abdullah bin Umar reported,

The Messenger of Allah ﷺ held a race between horses that had been trained for racing, sending them off from al-Hafya, with their finish line at Thaniyat al-Wada.I asked Musa, "How far was that distance?"He replied, "Six or seven miles."He also held a race between horses that had not been trained, sending them off from Thaniyat al-Wada, with their finish line at the mosque of Banu Zurayq.I asked, "How far was that distance?"He replied, "About a mile or so."Ibn Umar was among those who took part in that race.

Bukhari 2870

Sahih

حدثنا عبد الله بن محمد حدثنا معاوية حدثنا أبو إسحاق عن موسى بن عقبة عن نافع

عن ابن عمر رضي الله عنهما قال

سابق رسول الله ﷺ بين الخيل التي قد أضمرت فأرسلها من الحفياء وكان أمدها ثنية الوداع فقلت لموسى فكم كان بين ذلك قال ستة أميال أو سبعة وسابق بين الخيل التي لم تضمر فأرسلها من ثنية الوداع وكان أمدها مسجد بني زريق قلت فكم بين ذلك قال ميل أو نحوه وكان ابن عمر ممن سابق فيها

البخاري 2870صحيح
Contents
Reference
Commentary
Ayat
Collection
Sahih Bukhari
Book
Jihad and expeditions
Chapter
Extent of the race for trained horses
Numbering
Darussalam 2870
Bukhari 2870