The Messenger of Allah (ﷺ), used to recite this du'a when he was on a journey:

اَللَّهُمَّ أَنْتَ الصَّاحِبُ فِي السَّفَرِ وَالْخَلِيفَةُ فِي الْأَهْلِ اَللَّهُمَّ إِنِّي أَعُوْذُ بِكَ مِنْ وَعْثَاءِ السَّفَرِ وَكَآبَةِ الْمُنْقَلَبِ وَسُوءِ الْمَنْظَرِ فِي الْأَهْلِ وَالْمَالِ اَللَّهُمَّ اطْوِ لَنَا الْأَرْضَ وَهَوِّنْ عَلَيْنَا السَّفَرَ

Allaahumma 'Antas-saahibu fis-safari wal-khaleefatu fil-'ahli, Allaahumma 'innee 'a'oodhu bika min wa'thaa'is-safari, wa kaabatil munqalabi wa su'il manzari fil-ahli wal maali, Allaahummatwi lanal-arda wa hawwin alainas-safara

O Allah, You are the Companion in the journey, and the One Who looks after the family; O Allah, I seek refuge in Thee from the difficulty of travelling, finding harm when I return, and unhappiness in what I see coming to my family and property. O Allah, make the length of his journey short for us, and the journey easy for us.

Reference: Hasan Sahih (Albani). Abu Dawud: 2598