"The Prophet performed Salat towards his she-camel, or his mount, and he would perform Salat while on his mount, whichever direction it was facing."  

أَنَّ النَّبِيَّ ﷺ صَلَّى إِلَى بَعِيرِهِ أَوْ رَاحِلَتِهِ وَكَانَ يُصَلِّي عَلَى رَاحِلَتِهِ حَيْثُمَا تَوَجَّهَتْ بِهِ