There are a lot of items to be found in this area. Head to the camp (Survivors' Camp) first, we'll use that as starting point for all directions.
TIP: You can now fast travel back to the Summit Forest area to hunt some animals for extra XP. Daylight shines on the forest now, so they're not too difficult to spot.
Head to the waypoint to meet up with the crew. [400 XP]. You're supposed to check out the Galleon now, but there are various things to do in this area. First of all, you can converse up to three times with each crew member to get some additional dialogue. It's not much, but it reveals a bit more of their personalities, so you might find it interesting nonetheless.
Shipwreck Beach collectibles part 1 + Galleon.
The following things can be done in the Shipwreck Shore area right now:
• You can hunt some boar and seagulls to gain extra XP.
• In the harbor (close to the boat), unlock the closed door with your axe to find [DOCUMENT - #7 ENDURANCE CREW (JONAH: RECOGNIZING THE TRUTH)] inside.
• In the opposite building you can find another document on a desk: [DOCUMENT - #6 ENDURANCE CREW (REYES: ABOUT LARA)]. There's also some [RIFLE AMMO] in the corner.
• Climb this building to find a [GPS CACHE] in one of the corners on the roof.
• You can find some [SALVAGE] north of the northern building.
• There's also a [SALVAGE BAG] hanging north of the northern building.
• You can't open the iron door with rope (to the northwest) yet, so make a mental note of it and return to it later.
• There's a tank north of the harbor; north of that tank is a platform close to the large river that contains [SHOTGUN SHELLS], [RIFLE AMMO] and [SALVAGE].
• East of the tank is a large building with a cairn on top; inspect it to get the first of a series: [#1 CAIRN RAIDER].
• Southeast of this large builder is a broken down truck with some [SALVAGE] next to it.
• From the truck, move up the big sand walkway a few steps, until you can turn right/east around a large rock hill. The rocky walkway here leads to an [XP BOX] and a [#2 CAIRN RAIDER] at the very end.
• Move further up the hill via the sand walkway and take the left/northwest path. You can find an [XP BOX] on the far left, near a fence.
• Continue up the path and drop in the water when you reach the destroyed bridge. Destroy the barricade with your shotgun and push the buoy to the pond down below. You'll notice the climbable wall of the platform adjacent to this pond cannot normally be reached. Align one of the two buoys close to the climbable wall by using your rope arrows or pushing it. The second one should be placed between the dry, rocky ground and the first buoy so you can use it as stepping stone to reach the climbable wall. Up above you'll find the [#3 CAIRN RAIDER].
• At the very top of the sand walkway, to the right of the destroyed bridge, and near a tree, lies a [GPS CACHE]. You can find [SHOTGUN SHELLS] nearby a second tree.
• Head back down and go southeast of the truck. You can find some [SALVAGE] near the back of the large rock hill.
• There's a large mine to the east of here; you'll need to shoot ten of these to complete the area's collectibles. [#1 MINE SWEEPER]. Shooting them can only be done with guns.
• You can find a [GPS CACHE] next to this mine. (This is on the east rock wall).
• On the southeast side of the beach you can find a [GPS CACHE] underneath the wooden walkway adjacent to the building.
• 'Inside' the building is a [SALVAGE BAG]. You can find [ARROWS] on the pier.
• There's a [#2 MINE SWEEPER] on this (southeast) part of the beach.
• You can't enter yet, but there's also an optional tomb in the east part of the area, just south of the large rock hill (where you also found one of the cairns). Note it for later.
• Drop down on the beach. You can find a [GPS CACHE] next to the giant anchor on the west side of the beach.
• Look south, into the sea, to spot [#3 MINE SWEEPER].
• There's a sloop in the water that you can push (and pull with rope arrows) towards the large blue container to get on top. The reward? A lame [XP BOX].