Fallout 4 Guide: How To Find The Submarine

At a terminal in a military research facility out in the Commonwealth, you may have stumbled across the rumor of Chinese submarines, and read how they affected the outcome of the Great War. If that bit of foreshadowing intrigued you, then grab a Hazmat suit and some Mirelurk Cakes and head out to the coast.

North of The Castle and near the Four Leaf Fishpacking Plant, you'll find a pier that serves as home to a boy named Donny, who is looking out towards the ocean. Upon approaching him he will tell you that he has spotted a sea monster, and ask you to investigate. At this point the mission Here There Be Monsters will begin. Swim out into the water and find and enter the sub to continue.

Once inside, you'll meet the inhabitant of the submarine and go on a brief fetch quest to help them with their mission, to relaunch the Yangtze and head back to China. Your reward is a set of 3 homing beacons that you can use in combat to launch a tactical mission attack from the departing Yangtze.

The Yangtze is the second Chinese sub to be featured in the Fallout series. The other, SSN-37-1A, was featured in the Point Lookout DLC for Fallout 3. However, another Chinese sub is mentioned in Fallout 2; in San Francisco the descendants of the crew of a crashed Chinese sub have settled the area, and are referred to as the Shi.