This guide, along with the annotated level maps linked below, should help find any strongboxes you missed. If you are playing this level for the first time, you may want to follow the main walkthrough instead. Note that the specific items found inside some strongboxes will vary depending on the order in which you find them, so I have not listed the boxes' contents here.
The first strongbox is on the left as you enter the village. (screenshot) If you missed it the first time, fast travel back to the Valley Farmstead Base Camp, and you'll find the box at the top of the stairs to the the west, as shown here. See the map and walkthrough for details. (Click screenshot to enlarge.)
This box is inside the crumbling stone tower, just north of the blacksmith's cabin and east of the well in the middle of the village. Scramble up the wall into the tower to get it. (Click screenshot to enlarge.)
The next strongbox is down in the lower valley. It's sitting on the deck of the wooden structure a little ways east of the bear's den and the ladder leading back up to the village. There is also a rabbit for the Hung Out to Dry Challenge strung up nearby. See the map and walkthrough. (Click screenshot to enlarge.)
This strongbox is in the ruined building at the base of the zip line leading down from the spire where you light the warning beacon. If you missed it, return to the Ruins Encampment Base Camp, head up the hill, and you'll find this building on the way to the Physician's Crypt in the southeast corner of the map. See the map and walkthrough. (Click screenshot to enlarge.)
This strongbox is in the upper village where the Remnant set up a makeshift hospital after the battle with Trinity. (See the walkthrough and map.) To get back there later, fast travel to the Cathedral Courtyard Base Camp, climb the stairs, and then drop down into the village to the south. (screenshot) Head down the hill toward the second bonfire, and then go through the building to the east of the fire. (screenshot) The strongbox is at the south end of the clearing just before the broken bridge leading to THE ACROPOLIS. (Click screenshot to enlarge.)
This strongbox is in one of the cabins on the way down the hill from the Cliffside Lookout Base Camp. From the camp, grapple-swing across to the east, slide down the zip line, and then climb down to the cabin with the metal impact barrier. Use a grenade to destroy the barrier and you'll find the box inside. map/walkthrough (Click screenshot to enlarge.)
This strongbox is on the west side of the occupied village, under the wooden shelter near the Pumpkin Patch and document #22, which are marked on the map. To backtrack later, go to the Cathedral Courtyard Base Camp, climb the stairs, and drop down into the village. (screenshot) Head south, then west, through the village to find the strongbox. (Click screenshot to enlarge.)
†UPDATE HISTORY: 6/11/16 - Page first posted online.
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