Ibn 'Umar (May Allah be pleased with them) reported

Whenever the Messenger of Allah (ﷺ) mounted his camel for setting out on a journey, he would recite: "Allahu Akbar (Allah is Greatest)," thrice. Then he (ﷺ) would supplicate: "Subhanal-ladhi sakh-khara lana hadha, wa ma kunna lahu muqrinin, wa inna ila Rabbina lamunqalibun. Allahumma inna nas'aluka fi safarina hadh al-birra wat-taqwa, wa minal-'amali ma tarda. Allahumma hawwin 'alaina safarana hadha, watwi 'anna bu'dahu. Allahumma Antas-Sahibu fissafari, wal-Khalifatu fil- ahli. Allahumma inni a'udhu bika min wa'ta'is-safari, wa kaabatil- manzari, wa su'il-munqalabi fil-mali wal-ahli wal-waladi (Far removed from imperfection is the One Who has made this subservient to us, for we have no power to subjugate it, and certainly to our Rubb shall we return. O Allah, we ask You during this journey of ours for righteousness, piety and such deeds as are pleasing to You. O Allah, make easy for us this journey of ours and make the distance short for us. O Allah, You are our Companion during the journey and the Guardian of the family and the property in our absence. O Allah, I seek refuge in You from the hardships of travelling, unhappiness connected with ghastly scenes and evil turns in property and family)." When he returned, he recited this supplication making addition of these words: "Ayibuna, ta'ibuna, 'abiduna, li-Rabbina hamidun (We are those who return; those who repent; those who worship and those who praise our Rubb)."

[Muslim].