Sahih al-Bukhari 2870
Fighting for the Cause of Allah (Jihaad)
The extreme limit of the race of horses
Narrated Abu 'Is-haq from Musa bin `Uqba from Mafia from Ibn `Umar who said: "Allah's Messenger (ﷺ) arranged a horse race amongst the horses that had been made lean, letting them start from Al-Hafya' and their limit (distance of running) was up to Thaniyat-al-Wada`. I asked Musa, 'What was the distance between the two places?' Musa replied, 'Six or seven miles. He arranged a race of the horses which had not been made lean sending them from Thaniyat-al-Wada`, and their limit was up to the mosque of Bani Zuraiq.' I asked, 'What was the distance between those two places?' He replied 'One mile or so.' Ibn `Umar was amongst those who participated in that horse race."