Travel to the Aquarium
Once you've managed to get the boat and made it down to the bottom, look to your right to find some Supplements inside the trailer. Now continue through the building on your right and eventually you'll be forced to stop due to a gate blocking your path.
Here you'll want to go into the room on your right first to find a Trading Card 45/48 in a drawer, then head into the room upstairs to find an Artefact 75/117 by a body on the left. Move the trolley on the right to reveal a hole, then crawl through and jump down into the fenced of area, now input 70-12-64 into the Safe to find ammo.
Open up the gate and continue going down to the right until the boat cuts out. Restart the motor and hug the left path to find an open blue building with a workbench inside.
In the Field
Find 12 workbenches
Tip: If you have the spare Scrap, you may want to consider putting the 6x Scope on your Bolt-Action Rifle, as it'll massively help in the upcoming encounter.
Return to your boat and continue onwards until you see a building named Carthy Hotel, head inside to find an Artefact 76/117 by a body, then jump back on the boat until you reach an area full of enemies. Walk up the train on the left and use the rope to allow you to reach the locked section of the train.
Collect the Supplements and an Artefact 77/117 from the chair, then use this vantage point to take down the enemies below. Once the enemies have been dealt with, head up to 2F of the Kingsgate Brewing Co. building to find another Artefact 78/117 pinned to the wall.
Explore W&B Arcade
Get on your boat again and continue following the path until you W&B Arcade, here you'll want to collect an Artefact 79/117 from the table, then head upstairs to find some Scrap and a workbench. Head into the corridor and push the trolley towards the door to initiate a battle against a Bloater.
In order to defeat this enemy you'll want to put down Trap Mines around the arena and then use Molotovs to finish him off, as he's weak to fire. Once you've defeated the enemy, do a quick sweep around the room to find some ammo and healing items, then open the shutter to find a Trading Card 76/48 under the counter.
Head upstairs and go right to find an Artefact 80/117 pinned onto the wall, then go across to the other side of the room and remove the pipe from the chain, now open the gate and continue on to the Aquarium.