Allah, the Mighty and Majestic, says: "So whoever among you is ill or on a journey, then (let him fast) an equal number of other days." [Surah al-Baqarah: 184]
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصيام / Q8141
Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) narrated that the Messenger of Allah (peace and blessings be upon him) set out for Makkah in Ramadan in the year of the Conquest, fasting; when he (peace and blessings be upon him) reached al-Kadid, he broke his fast, and the people broke their fast with him. And they used to take the most recent, then the next most recent, of the commands of the Messenger of Allah (peace and blessings be upon him).
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصيام / 8141
Sayyiduna Ibn Abbas (may Allah be pleased with them both) said that the Prophet (peace and blessings be upon him) set out from Madinah in Ramadan with ten thousand Muslims, and that was at the completion of eight and a half years after his arrival in Madinah. He (peace and blessings be upon him) and the Muslims with him travelled while fasting, and when they reached the place called al-Kadid, which is between Usfan and Qudayd, he (peace and blessings be upon him) broke his fast and the Muslims broke their fast too. Then they did not fast for the rest of Ramadan.
Imam al-Zuhri (may Allah have mercy on him) said: Breaking the fast was the last of the two commands, and it was the Messenger of Allah (peace and blessings be upon him) who commanded it, and it is the last that is acted upon. Imam al-Zuhri (may Allah have mercy on him) said: Then the Messenger of Allah (peace and blessings be upon him) reached Makkah in the morning, when thirteen nights of Ramadan had passed.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصيام / 8142
Sayyiduna Hamzah bin Amr (may Allah be pleased with him) said: I said: O Messenger of Allah, I am an owner of riding animals; I look after them, travel on them and hire them out. Sometimes this month comes upon me, and I have strength and I am young. O Messenger of Allah, fasting is easier for me than delaying it so that it remains a debt upon me. O Messenger of Allah, shall I fast, which is greater for my reward, or shall I break the fast? He (peace and blessings be upon him) said: "O Hamzah, whichever of those you wish."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصيام / 8143
Mansur al-Kalbi said that Dihyah bin Khalifah (may Allah be pleased with him) set out from his village in Damascus, and that was three miles away; this journey was in Ramadan. Then he broke his fast and people broke their fast with him, while some others disliked it. When he returned to his village he said: "By Allah, I have seen a matter I never thought I would see: I have seen people turning away from the way of the Messenger of Allah (peace and blessings be upon him), and from the way of his Companions as well." He said this about those who had fasted. Then he said: "O Allah, take me to Yourself." Al-Layth said: What people have agreed upon is that they do not shorten the prayer nor break the fast except on a journey of four burud; in each barid there are twelve miles.
The Shaykh said: We have narrated in the Book of Prayer, from Sayyiduna Abdullah bin Abbas and Sayyiduna Abdullah bin Umar (may Allah be pleased with them), what indicates this. As for what is narrated from Dihyah al-Kalbi, if it is authentic, then it is as though he followed the apparent meaning of the verse granting the concession on a journey, and by his saying 'they turned away from the way of the Messenger of Allah (peace and blessings be upon him) and his Companions' he meant in accepting the concession, not in the estimation of the journey in which he broke his fast. And Allah knows best.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصيام / 8144
Nafi' narrated from Sayyiduna Ibn Umar (may Allah be pleased with them both) that he would go out to the forest (al-Ghabah), yet he would neither break his fast nor shorten the prayer.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصيام / 8145