The settlement was formed in the Museum of History, among the remains of a special exhibit showcasing different views on the afterlife. Banners hang on either side of the entryway that read, "an exhibit on death and the afterlife" and the entryway itself is marked "Underworld Journey."[Non-canon 2][Non-canon 3]
The ghouls that live here are a group of disenfranchised inhabitants of the Capital Wasteland. They are wary of strangers, but extend their welcome to visitors, so long as they behave themselves.[Non-canon 4] The group isn't bothered by the super mutants outside, but resent the Brotherhood of Steel for causing conflict in the area.
A ghoul named Willow patrols the exterior of the museum. A Brotherhood of Steel outpost is located nearby, and there are super mutants across the road in the Mall. The settlement has a bar, inn, clinic, general store, and hair stylist.
Immediately inside of the entryway is a large statue. Tulip's general store, Underworld Outfitters on the left and Winthrop's office to the right in the back corner. Doctor Barrows' clinic and the Chop Shop are located on the far wall. Heading up either set of stairs will take the Lone Wanderer to the second floor balcony. On the left is the Ninth Circle, a bar run by Ahzrukhal. On the right is Carol's Place, where the player character can rent a room or purchase food.
If Megaton was destroyed without finishing the quest Wasteland Survival Guide, Moira Brown may be selling miscellaneous items in the large room at the end of the overlook. The Lone Wanderer may also resume helping her with the Wasteland Survival Guide. Between the two upper-level establishments there is Snowflake, the resident barber, who is desperate to work with "a full head of hair" and wants to give the player character a haircut.
- ¹ Unconscious if Reilly's Rangers quest is active
- ² If she survives Stealing Independence
- ³ If she survives destruction of Megaton
- ⁴ If freed from his prison cell during the Finding the Garden of Eden quest.
- A Replicated Man holotape can be found in Winthrop's maintenance room on his desk. There can also be another holotape in Tulip's shop.
- Tulip sells a schematic for the railway rifle.
- There are five boxes of Sugar Bombs - Three are in Tulip's shop to the right of the bed on a shelf. There are two more on the very top of the shelf behind the combat helmet behind the counter, and the remaining two are in Carol's Place on a desk behind the main counter and a table in the sleeping area.
- A bottlecap mine - On Tulip's workbench.
- Sydney's 10mm "Ultra" SMG - Can be given to the player by Sydney if one finds A note from Little Moonbeam's father.
- Right before entering the doors to the Underworld concourse, the Lone Wanderer is facing north. However, once actually inside, they are facing south.
- If the player character decides to blow up Megaton, Moira Brown will survive and come to live in Underworld, unless the Lone Wanderer has already completed the Wasteland Survival Guide quest, in which case she will remain at the Megaton ruins.
- If Moira dies on her way to Underworld, her locker (labeled Craterside Supplies) might become glitched into the wall outside the doors of the Ninth Circle. The player character will still need her key to open it.
- If the Lone Wanderer does not recruit Fawkes as a companion, he will appear just inside the museum's entrance after the player character speaks to him outside Raven Rock.
- Charon can be recruited here, although doing so will result in the death of one of the Underworld's inhabitants, Ahzrukhal.
- If the Broken Steel add-on has been installed, Griffon will set up his Aqua Cura presentation outside after the quest "Take it Back!".
Underworld appears only in Fallout 3.
Behind the scenes
- The large painting on the second floor of the concourse is the real world "Dante and Virgil in Hell" by William-Adolphe Bouguereau.
- Also relating to Dante and Virgil, the bar "Ninth Circle" is phrased after the travels of Dante and Virgil through the nine circles of hell in Inferno.
- Fallout 3 loading screen: "Underworld was formed in the remains of the Museum of History's special exhibit, which showcased different civilizations' views on the afterlife."
- Fallout 3 loading screen: "Underworld has become a haven for disenfranchised Ghouls throughout the Capital Wasteland."
- Fallout 3 loading screen: "The Ghouls of Underworld generally aren't bothered by D.C.'s Super Mutants, but resent the Brotherhood of Steel for turning their back yard into a warzone."
- Fallout 3 Official Game Guide Game of the Year Edition Wasteland Census p. 69: "Doctor Barrows is also mayor of Underworld, although, because of the small nature of the town, his civic duties take a back seat."
- Fallout 3 Game of the Year Edition Tour of the Capital Wasteland p. 437: "Although the museum's facade is crumbling, the building is still a spectacular example of pre-apocalypse architecture. Head inside through the pair of ornate wooden doors."
- Fallout 3 Game of the Year Edition Tour of the Capital Wasteland p. 437: "You can visit two separate locations: the museum's lower halls, and the Ghoul stronghold known as Underworld. As you might have guessed, the latter's entrance is under the giant skull in the north wall."
- Fallout 3 Official Game Guide faction profiles p. 43: "The Underworld Ghouls are a group of refugees who have taken up residence in the remains in the Museum of American History. They mostly keep to themselves, doing their best not to draw attention from the outside world and its prejudices. They are known to welcome visitors, so long as those visitors behave themselves. But even as they welcome newcomers, the Ghouls of Underworld are cautious and wary of strangers. Each was subject to abuses by humans in the past, and as a result, their trust is easily revoked."