Recruit Deacon, mod clothing and get the Deliverer, one of Fallout 4's best guns.

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There are four factions in Fallout 4 (and Fallout 4 VR), and it's surprisingly not the shadowy Institute that is hardest to make friends with.

To join the Railroad, you need to trigger a hidden quest, finish the quest despite its refusal to give you any clues, and then complete an initiation mission.

The rewards are well worth it. Joining the Railroad allows you to recruit Deacon as your companion; to get the awesome Deliverer weapon; and to mod clothing. Let's talk it through.

How to finish Road to Freedom

For some people, the pertinent question may be "how to start Road to Freedom". This quest can be triggered in a number of ways, but if it hasn't already slid into your quest log, try hanging around outside Nick Valentine's detective agency; the NPC's that frequent this location will often chat about the Railroad, which will give you the first step.

The initial quest marker for Road to Freedom is in Boston Commons, near Park Street Station and the Swan Pond (watch out for the Swan). There's a hand-painted sign indicating the start of the Freedom Trail and urging you to look for the lantern at trail's end. After that, you're on your own, told only to follow the Freedom Trail.

Luckily, the answer is simple: the Freedom Trail is a tourist path indicated by red tiles on the pavement, leading away down the street near the sign. All you have to do is follow the red line, which has been painted in where necessary.

It's easier said than done, of course, as it often disappears under detritus. Remember it's a pedestrian path, so it never goes up on-ramps to highways, or passes under them, and you shouldn't have too much trouble - although you will travel through some very dangerous areas.

You don't even have to actually follow the trail; you can just proceed to the end, which is the Old North Church. This dungeon is found in the north east corner of Boston, near the river bank. Watch out for ghouls inside!

How to solve the puzzle in the Old North Church

Once you enter the Old North Church proceed into the main room and take a sharp right. You should spot a painted lantern symbol above a tunnel leading into the catacombs below.

Follow the tunnels and you'll eventually reach a dead end with a circular device on the wall. You can twist the ring clockwise or counterclockwise by highlighting various parts of it, and push the button in the middle. You need to spell out the word "railroad" by highlighting the appropriate letter, then pushing the button after each letter.

When the door opens, proceed in to meet the Railroad.

Joining the Railroad, recruiting Deacon, getting the Deliverer

Make nice with the Synth sympathisers and they'll invite you to show your mettle. This opens the mission Tradecraft, a lengthy dungeon crawl with loads of Synth enemies and some great treasure.

When you complete Tradecraft you'll be offered the chance to officially join the Railroad, and recruit Deacon as a companion.

You'll also receive the Deliverer. This unique 10mm pistol is a beast if you have a decent Agility stat; you'll be able to use VATS almost continuously. Mod it up with a suppressor and various damage modifiers, grab the Action Boy/Girl and Gunslinger perks, look for VATS-enhanced armour pieces, build up your Agility and Perception and you'll be unstoppable.

Finally, if you do a few more missions the Railroad will offer to help you mod clothes, a crafting system otherwise largely unavailable (Vault suits are the exception).