The Prophet ﷺ saw a man who had been put in the shade and saw a crowd of people around him (in the course of a journey). He said: Fasting while on journey is not part of righteousness. (Using translation from Abū Dāʾūd 2407)
أَنَّ رَسُولَ اللهِ ﷺ رَأَى رَجُلًا قَدْ ظُلِّلَ عَلَيْهِ قَالَ لَيْسَ مِنَ الْبِرِّ أَنْ يَصُومَ فِي السَّفَرِ