|This page is about the location. For the quest with the same name, see Oasis (quest).|
Fallout 3 locations project
Oasis is a settlement located north-west of Clifftop Shacks in the Capital Wasteland. It is unusually full of trees and green plants. Birds can also be heard once inside the gate, suggesting that animal life has since been flourishing here.
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. 
Oasis was originally a mine, but after the Great War it became just another part of the wastes. This was until Harold, a special mutational product of the Forced Evolutionary Virus, arrived. Harold possessed a tree growing on his head which he called Bob (and at times "Herbert" because, as he says, "Bob hates it") and eventually found himself overwhelmed by Bob and became rooted to the ground during his travels in the Capital Wasteland region after 2241. Here, he was discovered by several people who began to worship him as a god, and a small and exclusive cult known as the Treeminders began to form in secrecy. Bob began to blossom (which Harold apparently finds embarrassing) and many plants grew in this area, which became green with life, a stark and dramatic contrast to the rest of the wasteland.
Oasis is situated almost at the top center of the map. It is surrounded by steep cliffs, and can only be entered through a small gorge by traveling west to east. The entrance is small and can be easily missed; use the compass for assistance.
It is possible to get the coordinates of the Oasis by killing the Drifter at Dickerson Tabernacle Chapel. There are also a pair (or more) of wandering wastelanders found in a random encounter who will disclose the location, before attempting to kill the player, as well as a hallucinating wasteland merchant who promptly dies after being talked to.
 Notable loot
 Sunken chambers
As you enter in sunken chambers, turn left and up in a small room you will find:
- D.C. Journal of Internal Medicine nearby an orange glowing hole in the wall (inside a wooden box with the baseball glove).
- 1 pre-War book; (on the trunk next to the table).
- 1 Stealth Boy (on the table between chems).
At the bottom of the northern pond you will find:
- 1 mini nuke standing on an underwater rock near the middle of the pool;
- Various items of small importance (Mentats and combat knife).
 Damp cave
As you enter from the sunken chambers, you will find a missile, a paint gun, and a leaf blower on the ledge. On land, continuing around right side of cave you will find:
- 1 Nuka-Cola Quantum.
- A sniper rifle, on the far end in the middle near some rocks, light up your Pip-Boy to see it. Look for a skeleton and an ammunition box.
- Various items of small importance (2 fission batteries found by some tires, 2 Nuka-Cola bottles and a conductor nearby on the left side by more cave fungus).
- As you're exiting this cavern if you look right there will be (10mm pistol, 10mm ammunition, conductor and a stimpak).
 Related quests
- Three Dog will make a mention of a tree-filled place in the Capital Wasteland as one of his news items, although he admits he "may have been experimenting with jet" at the time.
- 'The Preacher' in the Downtown D.C. area Seward Square yells "Trees to the north" during one of his insane rants, and is probably referring to Oasis.
- In the grove where Harold is, it is possible to get behind the gates leading into the center of Oasis.
- If you have Red, Shorty, or Sydney as your followers they may not show up outside of Oasis upon exiting. Fast-traveling will fix this problem.
- Sometimes a herd of mad brahmin will spawn in front of the entrance but will not chase you all the way to the gate.
- Coordinates to Oasis can be found on the drifter at the Dickerson Tabernacle Chapel.
- It is possible that certain dialogue options will disappear after completing the main Oasis quest, making it impossible to obtain your reward. No reason for this is known, but may have something to do with certain dialogue choices made prior to completion of the quest.
Oasis appears only in Fallout 3.
- 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."