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If anything, this place will become a memorial to Him lest we may forget.Tree Father Birch

Oasis is a location in the Capital Wasteland in Fallout 3.


What came to be called Oasis was once just one of many mines scattered across the landscape of the United States before the Great War. The extensive network of caves beneath it was used as an impromptu shelter by the inhabitants of a nearby mining town from the bombs. As time passed, the sheltered rocky vale was stripped of mining equipment and other installations, with only a handful of artifacts surviving to the 23rd century.[1]

Sheltered by the rock formations in its northern surroundings, it gained a new lease on life in the 2240s/2250s when Harold, a human turned into a mutant by the Forced Evolutionary Virus, found himself overwhelmed by Bob, a tree sapling that had been growing on his head. "Bob" laid down roots in the area where Harold was forced to remain for decades[2]. Gradually, as Bob grew to encompass Harold's body, the tree also began to bloom and sprout pods that then scatter fertilized seeds around the area when blown by the wind, during what the Treeminders call the Harvest Month, generating new, living trees and giving life anew to Oasis.[3]

As Harold's mutation progressed further, he became the unwilling heart of a genuine oasis in the desolate wastelands.[4][5] Around 2257, a small cult formed under Birch, called the Treeminders with him as "Tree Father", dedicated to the worship of Harold as "the Great One". Birch saw in Harold, not an unfortunate mutant condemned to live out his life as a tree, but a god rooted to the earth and infusing life where there was once only ruin. As more came to join Birch's group, he decided that the Treeminders were to be Harold's last line of defense from those who would exploit or destroy him.[6]

In their dedication to preserving Oasis' beauty, the Treeminders shun most forms of technology in favor of nature, blaming technological progress for all of humanity's misery.[7] The cult's leadership is exercised by the Tree Father and the Leaf Mother (Birch and Laurel, respectively), with an equal say in its affairs.[8] As the settlement of Oasis grew and nature once again reappeared in the wasteland, the Treeminders were forced to confront the reality of the wasteland's other, hostile residents. Although they disdained technology, the Treeminders were obligated to make limited use of firearms to remain on equal footing with their neighbors.[9] Only select outsiders were permitted to live long enough to enter Oasis and meet the Treeminders, though it was rare. Most are turned away, some are killed when they try to gain entry by force, and others are shot on sight, like raiders, to preserve Oasis' solitude and safety.[10] By 2277, the arrival of the Lone Wanderer marks the first time an outsider has been allowed to enter the inner vale of Oasis in years.[11]

In the rare occurrence of a visitor being granted privilege to enter the settlement, the Treeminders ask that the new arrival drink sap in a ritual to purge them of all evil that might be inside, so that "He" may go unharmed, whereupon they are allowed to converse with "the Great One" after completing the ritual.

Centuries after the bombs devastated the former capital of Washington, D.C., Oasis is one of the most fertile places in the wasteland, filled with lush vegetation, healthy leafy trees, and even birds and squirrels living within the sheltered forest.[Non-game 1] No other place in the Capital Wasteland is so teeming with life,[12][13]


Situated to the northwest of the clifftop shacks in the northern part of the Capital Wasteland, west of Old Olney, the Oasis is located inside a large rock formation where the gate to enter it is accessed via a narrow passage in its western face.

The Grove[]

Main article: The Grove

The Grove is a small part of Oasis that is surrounded on all sides by trees and cliffs. This area can only be accessed after the Lone Wanderer has taken part in the ritual. It is entered via a wooden gate that comes from the pavilion after it has been unlocked. In the middle, the talking tree, uniting Harold and Herbert/Bob, can be found. To the southeast, a small radioactive pond can be found. If the Lone Wanderer dives in the pond, an Easy locked hidden underwater door can be seen, which leads to the damp cave.

The Caves[]

The damp cave is a cave that connects the Grove with the sunken chambers. It is accessed via an Easy locked underwater door from a pond in the grove. Inside there is a small contaminated lake (5 rads/sec) with a few level-dependent mirelurks. There are several junk items floating on the water of the small lake and on the bottom of the small lake. Several skeletons can be found underwater.


Notable loot[]


Oasis caverns map

Caverns map

Sunken chambers[]

Oasis sunken chambers map

Sunken chambers map

  • D.C. Journal of Internal Medicine nearby an orange glowing hole in the wall (inside a wooden box with the baseball glove).
  • One pre-War book, on the trunk next to the table.
  • One Stealth Boy, on the table between some chems.
  • At the bottom of the northern pond, one mini nuke.
  • Past the northern pond, at an intersection marked by green glowing fungi, a Stealth Boy.

Damp cave[]

Oasis damp cave map

Damp cave map

  • On land, continuing around the right side of cave, one will find a Nuka-Cola Quantum.

Related quests[]


  • Three Dog mentions the Oasis on Galaxy News Radio, describing it as having "real trees. Brown bark, green leaves, photosynthesis, all that good stuff."[14]
  • If one completes the Oasis quest by burning Harold, Three Dog will comment on a forest fire in the area where the "kid from Vault 101" was just seen.[15]
  • In the Grove where Harold is, it is possible to get behind the gates leading into the center of Oasis.
  • Coordinates to Oasis can be gained via the drifter at the Dickerson Tabernacle Chapel, or either the Oasis merchant or Oasis raiders 'Type A' random encounters.
  • Unlike in most settlements where provoked residents will stop fleeing after one's weapon is holstered, the residents of Oasis will remain permanently hostile after being attacked the first time.
  • All the human residents of Oasis have a name related to horticultural terms.


Oasis appears only in Fallout 3 and in Fallout Shelter Online.

Behind the scenes[]

The GECK editor suggests Oasis was once part of the wasteland rather than separate world space. There's an inaccessible door where Oasis is located in the wasteland called "OasisDoorFromWastelandToHarold."


Playstation 3Playstation 3Playstation 3 It is possible that certain dialogue options will disappear after completing the main Oasis quest, making it impossible to obtain your reward. There is no known reason for this, but it may have something to do with certain dialogue choices made prior to completion of the quest. [verified]



  1. The Lone Wanderer: "Any information you could give me on the caves below Oasis would be helpful."
    Linden: "Oasis is located near what used to be an old mining town before the bombs fell. When the attacks started about 200 years ago, many people took shelter in the natural caves that dotted the area. The old gate that stands at the mouth of Oasis Cave is the last piece of architecture from those days."
    (Linden's dialogue)
  2. The Lone Wanderer: "You don't actually seem that sad. Why do you want to die?"
    Harold: "I've been literally rooted to this spot thanks to Bob for maybe twenty or thirty years... I can't even remember anymore. Can you imagine being stuck in one place for that long not being able to eat or to read or to sleep or anything? In the meantime, I have these Treeminders bothering me every day about things I don't even care about. I can't stand it anymore."
    (Harold's dialogue)
  3. The Lone Wanderer: "How is it you're causing all of these things to grow around you?"
    The Lone Wanderer: "What's causing this place to grow?"
    Poplar: "In what we call the Harvest Month, the Great One creates seeds among his branches within seed pods. At the end of this time, the pods open and the seeds are carried quite easily upon the wind. It's quite beautiful. Wherever the seeds take purchase, they grow into trees, plants, grass or all manner of wonderful things."
    (Poplar's dialogue)
  4. The Lone Wanderer: "How is it you're causing all of these things to grow around you?"
    Harold: "It's kind of embarrassing really. Once a year, Bob decides he's going to go ahead and start growing these weird pods filled with tiny seeds. Well, all it takes is a good wind and the seeds just fly everywhere. I call them Herbert's Seeds. He hates that!"
    (Harold's dialogue)
  5. The Lone Wanderer: "Why do you call yourselves Treeminders?"
    Birch: "We care for this place and keep it safe from those who would seek to exploit it. He gives to us, so we give back to Him. It's an arrangement that's worked well for almost two decades. We shun technology and embrace nature. That's the life of a Treeminder"
    (Birch's dialogue)
  6. The Lone Wanderer: "How did the Treeminders begin?"
    Birch: "When I first beheld the glory of the Great One, I knew there'd be others who would seek to do Him harm. I also knew He would be calling others that he felt were pure of heart to protect Him. Right then and there I created the Treeminders... the Great One's last line of defense."
    (Birch's dialogue)
  7. The Lone Wanderer: "I think you're all a bunch of lunatics."
    Birch: "Ha ha ha. I don't expect you to understand everything you see here. After all, you carry the taint of technology upon you. Treeminders shun technology and embrace nature. All technology has brought the world is violence and death."
    (Birch's dialogue)
  8. The Lone Wanderer: "Were you aware that Laurel gave me this Liniment?"
    Birch: "Of course I am. I know everything that goes on in Oasis. Laurel is free to pursue whatever path she chooses. A long time ago, it was agreed that the Tree Father and the Leaf Mother hold equal say. I don't seek to change those customs. I just hope that when the time comes, you'll make the right choice."
    (Birch's dialogue)
  9. The Lone Wanderer: "If you hate technology, why carry weapons?"
    Birch: "Sadly, the Wasteland is a hostile place and sometimes we're forced to defend ourselves against it. If that means fighting with manufactured weapons, then so be it. Had He not asked to see you, you never would have gotten this close to the gates."
    (Birch's dialogue)
  10. The Lone Wanderer: "How do the Treeminders normally handle other Outsiders?"
    Birch: "If the Outsider doesn't have His blessing, we simply deny him entry to our home. If they persist on trying to gain entry, or display any hostile act that could potentially harm the Great One, we take action. If the Outsider were a Raider or some other nefarious type, we ensure they don't report our location back to their comrades."
    (Birch's dialogue)
  11. The Lone Wanderer: "Which brings us to why I'm here, I suppose."
    Birch: "Yes. Indeed it does. Sorry I don't speak to Outsiders very often and I tend to get lost in conversation. As you approached Oasis, He said you were coming and I was sent out to meet you personally with a request. He wishes to meet with you. You'd be the first Outsider to do so in a very long time."
    The Lone Wanderer: "So what was all this about meeting someone?"
    Birch: "Yes, my apologies. I don't speak to Outsiders very often and I tend to get lost in conversation. As you approached Oasis, He said you were coming and I was sent out to meet you personally with a request. He wishes to meet with you. You'd be the first Outsider to do so in a very long time."
    (Birch's dialogue)
  12. The Lone Wanderer: "Amazing, this place seems so abundant with animal life."
    Birch: "The innocent creatures are drawn here by His gifts. They come from across the Wasteland to live in this sanctuary. This part of the world is healing, my friend, and it's all thanks to Him."
    (Birch's dialogue)
  13. There are sounds of birds, crickets and squirrels as background sounds in Oasis.
  14. Three Dog: "Here's a question for all you faithful listeners. Have you guys and gals ever seen... a tree? No, no, no. Not those shriveled black things. I’m talking real trees. Brown bark, green leaves, photosynthesis, all that good stuff. Now what if I, the all-powerful Three Dog, were to tell you that somewhere right here in the Capital Wasteland, there’s a place with LOTS of trees. A veritable Oasis of green in that depressing sea of brown. Look, it was years ago, and I MAY have been experimenting with Jet at the time, but I’m telling you, it’s out there..."
    (Three Dog's dialogue)
  15. Three Dog: " You heard it here first, children. A forest fire in the Capital Wasteland, where all the trees were ALREADY burnt to a crisp 200 years ago. Point 1: The kid from Vault 101 was seen in that area just before the fire. Point 2: The smoke and smell from this thing don't match your typical chemical burn. Reports are, this smells like burning... wood."
    (Three Dog's dialogue)


  1. Fallout 3 Official Game Guide Game of the Year Edition p.319: "Oasis is a fertile, verdant dot in the center of all the desolation. This odd hidden vale is home to a strange, tribal-like people who call themselves the Treeminders. You are welcomed into Oasis with open arms, and their leader, Tree Father Birch, invites you to meet their god. Oasis is tucked away inside a giant rocky outcrop in the mountains just northeast of the monorail and freeway skeletons, and the entrance is close to a rope bridge."