This guide, along with the annotated level maps linked below, should help find any murals you missed. If you are playing this level for the first time, you may want to follow the main walkthrough instead.
The first mural is inside the Astronomer's Crypt just below the Installation Vista Base Camp. Fast travel there, slide down the zip line, and look for the crypt entrance on the right side of the path leading down toward the train yard. The mural is on the left side of the main passageway. See the walkthrough and level map for details. (Click screenshot to enlarge.)
This mural is just outside the building where you found the REVOLVER. Fast travel to the Train Yard Base Camp and climb through the opening in the wall with the red stars to the southeast. The mural is here on the left wall. See the walkthrough and level map for details. (Click screenshot to enlarge.)
On the map, this mural looks like it's also in the old sawmill, but it's actually underground, in the tunnel leading to the Ancient Cistern Challenge Tomb. The walkthrough has details. (Click screenshot to enlarge.)
This is in the northwestern part of the Gulag in the building just before the train tracks. To return later, fast travel to the Gulag Base Camp. Then follow the instructions in the walkthrough for revisiting the TRAIN TRACKS. Before you reach the tracks, you'll pass through a building with several dead Trinity soldiers. Go down the stairs and outside. Then turn around to spot the mural. (Click screenshot to enlarge.)
This ancient mural is in the tunnel leading to the Forge's Crypt. The tunnel entrance is north of the Logging Camp Base Camp on the other side of a broken wooden bridge. You can also reach it by climbing down the cliff from the Hidden Refuge Base Camp. See the map and walkthrough for details. (Click screenshot to enlarge.)
This Soviet crest is a few steps southeast of the Copper Mill Yard Base Camp. If you missed it the first time, just return there from any other fast travel camp. (Click screenshot to enlarge.)
This mural is in the Red Mine Challenge Tomb in the Copper Mill area. If you missed it, fast travel to the Excavation Shaft Base Camp, jump across the pit to the northwest, go up the stairs, climb onto the ledge where Lara is standing in this screenshot, and then use the horizontal pole to swing across to the mural. Check the map and waltkhrough if necessary. (Click screenshot to enlarge.)
This mural is in the Copper Mill, in the building northwest of the one where you first learn to craft molotov cocktails. After completing the level, return to the Copper Mill Yard Base Camp and climb up following the route in the walkthrough. The mural is on the northeast wall of the room with the chute leading down to the building below. (Click screenshot to enlarge.)
After you discover the Copper Mill Bridge Base Camp and unlock BROADHEAD CLIMBING ARROWS, about two-thirds of the way through the game, use climbing arrows to reach the ledge above that campfire. The mural is on the wall there. See the map and walkthrough for details. (Click screenshot to enlarge.)
†UPDATE HISTORY: 4/24/16 - Page first posted online.
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