Millhaven

"Whiskey Deltas capable of jumping heights of thirty feet or more. The walls of this compound are twenty feet Lt. Mora. If I didn't know better, I would say your report was tailor made to foster dissention in my ranks."

- Major Everly

Millhaven is a military outpost first mentioned in the Left 4 Dead comic The Sacrifice, based on the DLC campaign of the same name. Bill, Zoey, Francis, and Louis are taken to Millhaven after they are rescued by the Military at the farmhouse. Once they arrive, the Survivors are woken up and ordered at gunpoint to leave their weapons behind and are marched out of the rescue vehicle where they are met with aggressive military personnel, who immediately do not get along with Francis and threaten to shoot anybody who tries to run away. A military personnel tells them they are going to "testing," which is a series of tests run by a doctor to see if people are Carriers, which Zoey reacts to nervously. The military lock Francis and Louis up in a cell together and sends Zoey and Bill to a doctor. The military personnel guarding Louis and Francis's cell ask them what they saw since they've been fighting &quot;Whiskey Deltas&quot; or &quot;Walking Dead&quot; for two weeks and want to know if the Infected are mutating. It is confirmed that they don't know anything about the Special Infected and the commander of the outpost doesn't believe in the abilities they have, or even of Special Infected at all. Meanwhile, Zoey and Bill are being tested by a doctor to see if they are Carriers, which all four apparently are. The doctor decides to help Bill and Zoey escape while the two guards help Francis and Louis escape after a close encounter with a wandering Witch. They also encounter all the Special Infected (excluding Left 4 Dead 2 Specials) and the horde. In Part 3, most (or all) of the Millhaven staff is killed.

In The Parish in Left 4 Dead 2, it is stated that the Military is killing off any Carriers of the Infection. This might explain the large amount of dead bodies outside the outpost, unless they are the Infected. However, in The Sacrifice comic, it seems the military is simply trying to contain the Carriers so they cannot infect others, while testing them to try and get a cure to the Infection.

Staff at Millhaven

 * Major Everly ― the commander of the outpost. Concerned with keeping the base going and refuses to believe reports of Special Infected. Forcefully relieved of command in Part Two. He is killed when a Tank drags his helicopter out of the sky mid-flight, and causes it to crash.
 * Lt. Mora ― second in command; paranoid of Carriers; relieves Major Everly of command with force due to his concern over the base's safety. He is "left for dead" after an Infected manages to claw off his protective mask, scratching him in the process. His team refuses to pull him back up to higher ground, and he is left to fight alone. In the process of becoming an Infected, he encounters the Survivors and attempts to kill them. Bill quickly punches him to the ground, right before a Tank arrives and decapitates him.
 * Sergeant Downey ― Lt. Mora's confidant and fellow soldier. (Presumed dead)
 * Sergeant Hendricks ― part of Lt. Mora's squad who was ignoring orders from Major Everly, Sergeant Hendricks refuses to help Lt. Mora after his commanding officer lost his gas mask and was exposed to the Infected.
 * Soldier Jeff ― partnered with Annie, guarding the room holding Francis and Louis. Teams up with the two Survivors in the later half of Part Two. Noted with a purple speech bubble when talking in the comic. Leaves the team to rejoin a holdout area in Part Three, but it was overrun by the Infected. (Presumed dead)
 * Soldier Annie ― partnered with Jeff and also guarding Francis and Louis. Teams up with the two Survivors and takes them to the armory―noted with a red speech bubble when talking in the comic. Leaves the team to rejoin a holdout area in Part Three, but it was overrun by the Infected. She was last seen as the female soldier being attacked by the Infected at the end of Part 3. (Presumed dead)
 * Soldier Pena ― with Lt. Mora. (Presumed dead)
 * Soldier Brooks ― with Lt. Mora. (Presumed dead)
 * Soldier Davis ― with Lt. Mora. (Presumed dead)
 * Soldier Rivera ― threatens Zoey into giving a saliva sample, is disarmed and cowers from Zoey due to his fear of possible contamination from her―noted with a navy blue speech bubble when talking in the comic (with gas mask on). Going by his speech bubble color, he also seems to be the soldier who punches Francis and tells Zoey they are going to be tested. (Presumed dead)
 * Unnamed doctor ― in charge of making a cure for the Green Flu, which stops Zoey and Bill from being executed. Fears there may not be any cure at all, and tells the Survivors that they escape together. He is killed by a Smoker while the Survivors attempt to escape the complex.

There are other unnamed soldiers at the base who are promptly attacked by the Infected in the latter half of Part Two. One is mortally injured by a Witch, and another is seen who has turned into a Boomer and in the start of part three a Smoker-soldier is also seen.