Forzathons in Forza Horizon 5 are weekly timed challenges that offer up Forzathon Points. These points can be used to unlock some premium cars and cosmetics, to give you some new wheels to put to the test. This week, one of the challenges posed to players is to simply complete an expedition. There are a number of expeditions in the game, and all players have to do for the challenge is to complete one of them.
As Forza Horizon 5 cycles through challenges during Series 1 and beyond, the goal to complete an Expedition will pop up and you may not know exactly how to complete them again after the have finished them during the main story.