This mod adds a full sized Prewar Vault near Concord. There is a map marker you cannot miss. Vault-tec Workshop is required, as I have used the vault door from that DLC. It was the only way to make the door open AND close. Without it, the door would have been unable to close. The way this settlement is set up required me to actually make it into two separate settlements. You can send followers to either settlement and setup supply lines to others. Settlers showed up very quickly after hooking up a beacon. I got three settlers show up together within minutes.

ENTRY LEVEL SETTLEMENT
The entry level consists of a fully working Vault door which you can open and close whenever you want via your pipboy. Its pretty much guaranteed the attackers will not be able to harm your settlement in any fashion or form. Because I've placed all the attack spawn markers on the outside of the vault door. But that will only work if you dont forget to actually close the Vault door. But remember you will have to open it to let settlers in or out, because I made them spawn outside the door as well. It was the only fair thing to do. Plus it works for an added layer of immersion.
Again, the entry level is a separate functional settlement as there would have been no other way to send settlers there. There is no need to set up supply lines as long as you claim both workshops, they will share the same inventory, but NOT the same stats such as settler count and happiness.
The entry has a screening area, maintenance area, a security office, a small residential area for any security posted there. I have included 20 Vault Suits in official Vault-tec boxes. They should respawn Incase you need more.

IMPORTANT INFO:
I have fixed the issue with the workshops not showing up in the pip-boy, but...
You must enter or exit the vault from the exterior door at least once in order for it to register the settlements in your pip-boy upon taking ownership of the workshop.

Please let the Vault Door cycle finish either opening or closing before you leave the cell. That means wait for the lights and horn to turn off BEFORE either using the elevator to the main level, The door to exit or fast travelling out. Failure to wait will cause the script not to terminate and make the door unusable. YOU HAVE BEEN WARNED.

MAIN VAULT SETTLMENT 
You can build whatever you want there as I have used a full workbench. The Vault has a large Overseers office overlooking the Atrium, with a reception area, a clinic, a hydroponics room, a large area for growing crops, a classroom, a large cafeteria, a residential wing with men's and women's bathrooms. I haven't done too much inside along the lines of lighting. I did leave some things in the Vault so you wouldn't have to do to much guessing about what rooms are what. I have used signs where ever possible to help out on that front too. Scrapping mods should help you to take out whatever you don't want, but I make no guarantees because I haven't added anything to any scrapping lists. Additional 20 Vault suits in official Vault-tec boxes. They too should respawn Incase you need more.

POWER
I have made two wall mounted power generators, one is 3 power, and the other is 50 power. They can be found in the Generator section of the Power menu. Both radiate the power they produce as well as being able to connect power lines to them. Make sure to disconnect lines before moving them.

Water

Both settlements have 100 water supply already working and ready to go. If you need more water there is a large dirt area for planting you can put some water purification units onto. But 100 water should be plenty enough.

IMAGES
If you want to upload images of your settlement here you can as I have authorized you to do so. Let everyone see what your vault looks like. I'd like to see what everyone is doing with it too.
 
New updates

1. Added pip-boy crate contains 20 pip-boys.

2. Fixed settlement info displaying in your pip-boy. Read "Important Info" above if you haven't already.

3. Added some light to the atrium.


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