once
قَالَ جَابِرٌ رضي الله عنه: ((كُنَّا إِذَا صَعَدْنَا كَبَّرْنَا، وَإِذَا نَزَلْنَا سَبَّحْنَا)).
Meaning
Jabir said: Whenever we went up a hill we would say Allaahu 'Akber (Allah is the Most Great) and when we descended we would say Subhaanallaah (Glory is to Allah)
Source and references
Hisn al-Muslim, entry 214.The reference is copied from the edition; separate editorial verification is not complete yet.
Source edition: Fortress of the Muslim. Open source ↗