Smash the barricades to reach the mobs. Kill them all. Two Elena's Flags here, one beside the lookout tower before the bridge, and one by the tent between bridge and stage door.
Clear poochums and kobolds, smash barricade to left and clear archers. Enter the "picnic grove" for chest. Opening it calls the mobs (a troll and some enraged poochums).
Back in the clearing where you entered, clear the other barricade that was to your right and clear mobs to reach the next door and another troll with kobolds.