At this location, an ambush was set up by some of the rebels, to try to attack some of the militia as they approached Oulart Hill. While not much came of the ambush (no one was killed and it was spotted by the militia before it sprung into action), the ambush may well have bolstered the confidence of the rebels for the battle that was to follow later on in the day.
The cache is a small round plastic container, with room for small swaps and trackable items.