Expedition 5 is a location similar to Expedition 4. It is a partially ruined town with lots of components on ground around buildings. It can be found east of Spring and south of Reaver Camp.
This location was created by the Tech Hunters during their fifth expedition south. This location is referenced in Tech Hunter's Notes: The Ashlands. Although the number implicates that there were 4 expeditions before it, only the 4th one has an observable abandoned settlement, it's not explicitly stated in the game what the results of the other expeditions were.