Perhaps someone mentioned the Railroad in passing. Maybe you found one of their Holotapes. But whatever the case, you have a mission in your Pip-Boy log telling you to Follow The Freedom Trail, and you have no idea how to go about it. You've come to the right guide.
First head over to Swan Pond in the heart of the Boston's metropolitan district, where there is a Protectron who serves as the beginning of the Freedom Trail. The Freedom Trail is also the name for a tour of the city designed to hit up its major historical spots, and you will be retracing the steps to find the headquarters of the Railroad. Nearby is a sign that says "At Journey's End, Follow Freedom's Lantern". This is a reference to the small white symbols that the Railroad uses to send messages and communicate with other Railroad members; you will find them leading the way through your final destination to the locked door guarding the Railroad headquarters.
Listen to the Protectron give a brief history, then find the thin red line that runs along the road outside the park's gates. You will be following this through a few city landmarks. In front of each is a seal with a letter and number that will help you decipher the password. The first, 7A, is in front of the "At Journey's End" sign.
The red line is sometimes covered or obscured by debris, so you will need to look around to pick up the trail. For the most part, continuing in the same direction will help you find it again. The second stop is the Massachusetts State House, 4L.
The stop after that is Old Granary Burying Ground, where you'll find 2A.
The fourth stop is in front of Goodneighbor, where you'll find the seal labeled with 6O.
The sixth stop is Fanueil Hall (be careful, Super Mutants are always in this location). The seal is marked 5R.
The seventh stop is Paul Revere's House, where you'll find the seal marked 8D.
And the eighth and final stop is the Old North Church, where you'll see a lantern marked outside the front door and 1R written on the seal at the base of steps. Put in order, the letters spell out FREEDOM. Head inside.
Inside, kill all the Feral Ghouls and use your Pip-Boy to find the path down to the crypt below. Navigate the tunnels until you find the seal guarding the entrance to their lair.
The inner ring labeled The Freedom Trail Boston can be moved clockwise and counterclockwise. The button in the middle can be pushed. The direction you pull the ring in order to spell out the letters do not matter. You do not have to alternate between clock and counter clockwise, as you would on a padlock. You do, however, have to push the button after every letter. It also does not matter which letters you use to spell out RAILROAD, for example the seal in front of Old North Church has the R in Freedom labeled as the part of the passcode, however if you use the R in Trail instead, it will still work.
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