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Kimball, Caesar, House... you'd think their whole world was that wall, cutting the Colorado. If I'd never laid eyes on it, never spoke of it...Ulysses, Lonesome Road

Hoover Dam, also called the Old World Wall,[3] is a hydroelectric dam located in the Mojave Wasteland in Fallout: New Vegas that serves a pivotal role as the site of two major clashes in the course of the conflict between the New California Republic and Caesar's Legion.


One of the wonders of the pre-War Old World, the Hoover Dam crosses the Colorado River, impounding Lake Mead to the north.[4][5] The structure served as one of the most substantial sources of electrical power in the region before and after the Great War, protected with anti-aircraft weapons.[6][7]

When the Great War first broke out, some of Mr. House's networked mainframes and laser systems kept the Hoover Dam in almost untouched condition by disabling and/or destroying the incoming nuclear missiles, along with a majority of Las Vegas.[8] When House was put into a coma afterward, the plant was abandoned and left to the elements for nearly two centuries.

Post-War Revival[]

The Followers of the Apocalypse mentioned the continued existence of Hoover Dam as early as 2170.[Non-game 1] The Mojave chapter of the Brotherhood of Steel initially had plans to claim the dam themselves but became sidetracked by Father Elijah's experimenting with the power plant at HELIOS One.[9] In the meantime, scouts of the New California Republic arrived at Hoover Dam, causing Mr. House to spur into action at the sign of civilization.[10] House worried about the independence of his new city's power source, but the arrival of Caesar's Legion in the region meant that the NCR could not take the dam and the Strip without leaving them vulnerable to the Legion.[11] When the NCR arrived in the Mojave to the dam en masse in 2274, Mr. House was waiting with a force of his Securitrons and members of the Three Families, but not to fight, rather to negotiate. Through diplomacy, House and the NCR drew up the Treaty of New Vegas, legislating that 95% of the dam's power output would be sent to the inner territories of the NCR, the other 5% continuing to power New Vegas, and in return House would retain his sovereignty over the Strip along with providing unrestricted access to the casinos for NCR citizens.[12] Within a year of the treaty, the NCR had managed to get the dam running at 50% capacity.[13][14][Non-game 1]

First Battle of Hoover Dam[]

Around three years after the NCR occupied Hoover Dam, in 2277, the Legion, then led by the Malpais Legate, made their first substantial attempt to take the dam, but were defeated shortly after by Chief Hanlon, alongside NCR Rangers and First Recon sharpshooters, who performed a tactical retreat, placing explosives ahead of time to lead and trap the Legion's elite forces in Boulder City, then springing the trap and detonating the town, killing everyone in it, legionnaire and Ranger alike.[15] The result was General Lee Oliver being able to both successfully hold the dam and push back the Legion's main force, significantly enhancing his political clout.[Non-game 2][15][16]

Second Battle of Hoover Dam[]

By 2281, in order to weigh the outcome of the impending Second Battle of Hoover Dam in favor of the NCR, Colonel Cassandra Moore and General Oliver have fortified the dam and stationed a significant military presence to once again face the Legion.[17][Non-game 2] While troopers are active here, there are also a large number of civilian contractors and engineers who are trying to keep the dam running as smoothly as possible.[Non-game 2]


FNV Hoover Dedication Monument

Dedication monument

It is fitting that the flag of our country should fly here in honor of those men who, inspired by a vision of lonely lands made fruitful, conceived this great work and those others whose genius and labor made that vision a reality.— Hoover Dam dedication monument

Situated on the border between the former U.S. states of Arizona and Nevada, threading the Colorado River, Hoover Dam covers a large area with extensive exterior and interior sections, despite there only being one map marker for the entire location. Following the Colorado River downstream (or coming upstream from Cottonwood Cove), the player character will encounter a pontoon barrier.

Name Description
Western exterior The west side of the dam is controlled by the NCR and features the anti-aircraft gun seen on billboards. The fast-travel map marker puts the player character just outside of the entrance to the Hoover Dam visitor center along former Highway 93, south of the Nevada Spillway. Just north of the visitor center building are a stage and viewing area. To the west of the stage is a large anti-aircraft cannon. Across from the visitor center stands the Hoover Dam dedication monument.
Atop the dam Continuing north along the barricaded road leads to the top of the dam itself. Two towers are along the south edge of the road. Access to Hoover Dam Intake Tower 01 and 02 is via a bridge connected to the north side of the road. The road ends at a checkpoint door which is inaccessible until any of the final quests, such as Eureka!. The checkpoint contains a Very Hard locked terminal and a few lockers with minor loot. It also houses a small sniper nest on the roof, accessible via a ladder.
Base of the dam Access to the north and south bases of the dam is blocked off by a pontoon barrier constructed with toxic waste barrels, which holds sections of the chain-link fence in place along the top of the water. Weights keep the submerged ends in place and the whole structure taut. The south base of the dam is accessible by descending through interior sections of the dam and exiting from the second tier of either Hoover Dam Power Plant 02 or 04. There are spectacular gushes of water from outflow pipes high up on the east and west walls of the river canyon. It is possible to swim from the west to the east side and climb up on the concrete area by swimming all the way to the south end and walking up the sandbar to the southeast corner.
Eastern side

The east side of the dam is controlled by the Legion. Going west along the barricaded road leads to the top of the dam itself. Access to Hoover Dam Intake Tower 03 and 04 is via a bridge connected to the north side of the road. There are two towers along the south edge of the road; one is ruined. The Arizona Spillway is situated on this side of the dam, south of the roadway.



Notable loot[]

Related quests[]


  • The head engineer, Mike Lawson, shares that there used to be six turbines running but only four now function. Even though the player character can swim down to reach the turbines, they cannot be repaired.[18]
  • When on top of the first sniper tower, one can lock and unlock the ladder. However, it can be used either way.
  • The NCR Rangers walking on the dam do not wear NCR Ranger patrol armor, they wear a lower resolution variant. The insignia on the shoulder is blurry, the water pack on their backs is flat, and rifle-grip weapons do not change position when holstered. Much like the face masks worn by troopers, the armor cannot be looted from their inventory.
  • There are invisible walls around the area where Kimball speaks. If he is killed and his body ragdolls, this may result in his body flying and bouncing off the invisible walls.
  • Arcade Gannon will make some comments about the dam if brought there as a companion.[19]
  • The dam is one of the few locations with fresh water outside as well as inside. The water inside is marked as owned but inflicts 0 rads.
  • The dam is mentioned in an alternate ending for Dead Money ending as well as in the ending for Old World Blues.


Hoover Dam appears only in Fallout: New Vegas and is mentioned in its add-ons Dead Money, Honest Hearts, Old World Blues, and Lonesome Road.

Behind the scenes[]

A real-world map of the Dam and surrounding area, frequently seen in Fallout: New Vegas.
  • The in-game Hoover Dam is based on the real-world location of Hoover Dam, a concrete arch-gravity dam in the Black Canyon of the Colorado River, on the border between the U.S. states of Nevada and Arizona.
  • Hoover Dam's namesake is Herbert Hoover, 31st President of the United States who was in office at the time of its construction. It was briefly renamed to Boulder Dam during Theodore Roosevelt's presidency before reverting back to Hoover Dam in 1947.
  • Many sections and landmarks of the real-world Hoover Dam are seen in-game, including the visitor center's Winged Figures of the Republic sculptures (though it lacks the star chart mosaic).
  • The maps of the Hoover Dam scattered around the Mojave are blueprints created in the 1930s and can be seen in the University of Nevada Las Vegas Digital Collections.
  • On the side of one of the stone guard towers is a banner reading, "LEGION GO HOME." This is a reference to the real-life slogan "Ami go home," originally a protest from European communists against US occupiers after WWII, later adopted by European peace movements during the Vietnam War and more recently the Gulf War.
  • The other side of this is a reference to the film Monty Python's Life of Brian wherein the main character writes "Romanes eunt domus," grammatically incorrect for "Romans, go home." He is later corrected by a Roman centurion.[Non-game 3]
  • During the battle at Hoover Dam, most non-player characters wear masks. This was encouraged by Joshua Sawyer as an attempt to reduce memory usage and FaceGen/FaceFX expense.[Non-game 4]
  • A cut note from Fallout 3 references the dam being sabotaged.[Non-canon 1]
  • If one jumps on the artillery cannon, runs down the barrel and jumps, they can go past the game's barrier and go to the bottom of Hoover Dam. Just save before hitting the ground, then load a save. Facing the direction of the river, if one goes on the right side, they can find a door to the Hoover Dam power plant 2 and a door leading to power plant 4. Otherwise, this area of the map is inaccessible. There is an "exit door" in the northeast corner of plants 2 and 4, behind the metal stairway which ascends west to the top of the generator, that can be used to exit to the spillway. One of these doors is also used in the final quest.
  • At the base of the dam, while it is possible to get above the top of the chain link fence from the water, invisible barriers prevent the player character from actually hopping over it, even when attempted from the cliffs far above the barrier. However, it is possible to jump off the north side of the dam into the water. This places the player character on the opposite side of the pontoon barrier and allows them to swim the length of the Hoover Dam. However, using the console to toggle collisions, then continuing into the northern side of the dam's waters through the pontoon barrier, will cause the game to crash. A one-way ladder upwards is available to return to the top of the dam on the NCR side of the river.
  • If one jumps down from the Hoover Dam into the water on the north side, and swims as far east as possible until they can't jump/walk any farther, they may begin to hear artillery fire and flying shells even though they have not started the battle at Hoover Dam. In addition to the sound effects, the theme music of Hoover Dam will change to the version heard in one of the end game quests. This music is unique and will not play in any other location in the game.
  • If one jumps off the north side of Hoover Dam and returns to the top of the dam, the game may glitch and cause things like the artillery cannon to completely disappear and the texture for the road in front of the visitor center to change.

Cut content[]

Spare Us the Cutter
  • Hoover Dam originally featured active jet flow gates and water exhaust jets ejecting water into the Colorado River. Both were disabled pre-release, likely due to technical limitations: The jets are animated and the Gamebryo engine did not support animated LOD objects.
  • The Hoover Dam and the Legate's camp are connected by a long, winding road. It is not accessible, not navmeshed, and affected by a script that teleports anything caught inside to either the entrance gate at the Dam or the exit gate at the camp. Scripts suggest that the area was intended to be used to store reinforcements to be later sent into the battle, using a "conga line" system, but it was later disabled. A leftover trigger behind the gate spawning a pair of legionaries suggests that the road was at one point supposed to be an actual combat zone, but it is disabled in the released game, together with the whole area. There are also multiple crosses spread out along the road, some hidden behind level geometry, indicating that the area was simply cut to save on time.
  • If Julie Farkas is convinced to support the NCR, she mentions providing medical support. A Follower NPC exists as VFSFollowersDamDoctor, and his dialogue exists in VdialogueHooverDam, but is not placed in the game.
  • There's an unused empty map called "Arizona Spillway Tunnel" (HooverDamIntArizonaSpillway). The Arizona Spillway is a real part of Hoover Dam and is modeled in the game. It is used to remove excess water from the reservoir, with a long cylindrical tunnel that spills into the Colorado. There is an unusuable grate at the bottom of the spillway in the game, and the tunnel is present in the game (mostly obcured by cliffs and the rest of the Dam), which suggests it was to play a role in the second battle at one point or another, though the specifics are unclear.
  • Gun turrets would have been present at Hoover Dam. There are full scripts and messages (vHDLVLTurretScript, vHDTurretMessageNCR01, vHDTurretMessageNCR01b, etc) that show they would be initially disabled in the conflict, and the player could then repair them to help fight against the Legion.
  • There's a large amount of reworked/redundant code involved with the endgame fight. It's extremely difficult to unpick it all as there are several iterations/implementations of things like the reinforcement code as it was clearly realized having so many enemies in the area at once would kill console performance. It's difficult to separate what was abandoned from what actually works.



  1. Order of Withdrawal
  2. Bureau crest on Hoover Dam pamphlet
  3. Courier: "NCR would have needed this supply line open to reinforce the Mojave - and Hoover Dam."
    Ulysses: "The Dam. That Old World Wall."
    (Ulysses' dialogue)
  4. The Courier: "Whatever you believe happened, you have it wrong."
    Ulysses: "It was you walking that road that kept the Divide alive. It grew from what you did. Settlers... camps... filling that Old World city. Chance for a new nation, new beginning. New way of thinking. Could've breathed new life into the Mojave, bridging East, West. Like Hoover Dam... but not Old World, something you made. Road was a supply line."
    (Ulysses' dialogue)
  5. Old World Blues endings
  6. Courier: "What can you tell me about Hoover Dam?"
    Lt. Monroe: "It's one of the biggest sources of electrical power in the region, so the NCR's fortified the place pretty heavily. When President Kimball shows up on his inspection tour, I'm sure he'll be confident that the Dam is safe and secure."
    The Courier: "The President is coming to Hoover Dam?"
    Monroe: "It's probably just a political thing - you know, give a few speeches, shake hands with the troops, boost morale."
    (Monroe's dialogue)
  7. Rose of Sharon Cassidy: "Check out those guns - rumor had it they used to shoot planes down before the war."
    (Rose of Sharon Cassidy's dialogue)
  8. The Courier: "What preparations did you make to save Las Vegas?"
    Robert House: "On the day of the Great War, 77 atomic warheads targeted Las Vegas and its surrounding areas. My networked mainframes were able to predict and force-transmit disarm code subsets to 59 warheads, neutralizing them before impact. Laser cannons mounted on the roof of the Lucky 38 destroyed another 9 warheads. The rest got through, though none hit the city itself. A sub-optimal performance, admittedly. If only the Platinum Chip had arrived a day sooner..."
    (Robert House's dialogue)
  9. The Courier: "Why is the Brotherhood interested in Nevada?"
    Veronica Santangelo: "It was the Dam, really. We'd heard rumors it was working. Figured we could claim it, put it to use. And... it may also have been partly that our Elder at the time had worn out his welcome. Didn't end up mattering. We got sidetracked at HELIOS One and the NCR took the Dam in the meantime. We're still after it, though. In theory."
    (Veronica Santangelo's dialogue)
  10. The Courier: "How did you establish New Vegas?"
    Robert House: "We can discuss this in greater detail at another time. Suffice it to say that when my Securitrons detected NCR scouts at Hoover Dam, I took action. I recruited a tribal force to supplement my Securitrons and renovated the Strip just in time to welcome the NCR as it marched into the region. Instead of war, a treaty was negotiated. And the money started to pour in."
    (Robert House's dialogue)
  11. The Courier: "Wasn't the NCR's army big enough to defeat your Securitrons and the Three Families?"
    Robert House: "Indeed it was - and still is. But not without taking significant casualties. Would Kimball and Oliver have traded the lives of hundreds of soldiers for absolute control of Hoover Dam? Oh yes. They weren't afraid of me, they were afraid of Caesar - that attacking me would leave them vulnerable to a Legion offensive. And so they negotiated. Not out of the kindness of their hearts, as they try to make it seem. Because the calculus of power left no other choice."
    (Robert House's dialogue)
  12. Dennis Crocker: "In 2274, President Kimball sent the NCR army into the Mojave in force, with the objective of occupying and repairing Hoover Dam. Rangers and army scouts had confirmed that the dam was basically unoccupied and could be restored to an operable condition. Upon arriving at the dam, however, they discovered that a large force of tribals and robots had occupied it. This was our introduction to the Three Families, the Securitrons, and, of course, Mr. House. Using his Securitrons as intermediaries, Mr. House called for parlay. He claimed his forces had occupied Hoover Dam in order to safeguard it for our arrival. And that he was ready to turn it over to us, so long as we could agree to terms. Those terms became the Treaty of New Vegas."
    (Crocker's dialogue)
  13. The Courier: "Where does New Vegas get all its electricity?"
    Robert House: "Hoover Dam, of course. A hydroelectric dam? The NCR had it up and running at 50% capacity within a year of occupying the dam. By treaty, New Vegas receives 5% of its output - more than enough."
    (Robert House's dialogue)
  14. The Courier: "What can you tell me about Hoover Dam?"
    Cassandra Moore: "It's of immense strategic value to the NCR. Hoover Dam sends enough electricity west to light every city and major settlement. It's moderately defensible, with a single point of entry on the east side. To get to the power plants below, the enemy has to cross the entire top. The Legion's tried to cross the water on a few occasions, but slow-moving boats make easy targets for sharpshooters."
    (Cassandra Moore's dialogue)
  15. 15.0 15.1 The Courier: "What happened to Boulder City?"
    Monroe: "Destroyed during the Battle of Hoover Dam a couple of years ago. The town was set up as a trap for Caesar's Legion. The sharpshooters in the Rangers picked off the Legion's veterans from a distance, and the rest of the Legion just rushed on in. Then - boom!"
    (Monroe's dialogue)
  16. The Courier: "How did you end up as Caesar's legate?"
    Joshua Graham: "This way lies the path to hell. Edw- Caesar needed me to translate. Translation became giving orders. Giving orders became leading in battle. Leading in battle became training, punishing, terrorizing. A series of small mistakes before a great fall. And I stayed in that darkness until after Hoover Dam. After I failed Caesar and he had me burned alive, thrown into the Grand Canyon."
    (Joshua Graham's dialogue)
  17. The Courier: "General Oliver, Hoover Dam is ours. Leave at once."
    Lee Oliver: "I would sooner spit on the grave of my dead mother than let some courier-walk-the-wasteland-fuck talk to me like that. Who the hell do you think you are? Looking to cash your chips to the sound of NCR bullets, eh? I can oblige."
    The Courier: "Are you sure that's wise?"
    Lee Oliver: "Look, I know you're riding high right now, but let me tell you - you ain't pissing on me right now, you're pissing on the Bear. You been far enough West I'm guessing to know how far that claw stretches. Fuck with the Bear, and..."
    The Courier: "How about I ask these robots to fuck you and your entire battalion with a rocket barrage?"
    Lee Oliver: "Do you know what you're doing? Making a nation - like you think you're doing, ain't like chowing down on a pile of Fancy Lad Snack Cakes. Think you got the guts to carve out a frontier? Build towns, protect the roads, run supplies, train troops?"
    (Lee Oliver's dialogue)
  18. Courier: "How is the dam running these days?"
    Mike Lawson: "Been better, been worse. When I first came here there was but one turbine spinning. At one point shortly after the last battle I had six of them spinning, was a wonderful sound. Only four of them are running right now."
    (Mike Lawson's dialogue)
  19. Arcade Gannon: "Well, I'll be. Hoover Dam. One of the last remaining functioning wonders of the Pre-War world."
    (Arcade Gannon's dialogue)


  1. 1.0 1.1 Fallout: New Vegas Official Game Guide Collector's Edition p.458: "Controversy over the Vegas Frontier
    The NCR spread east into Nevada in large numbers just five years ago on a 'humanitarian mission' to 'bring the light of civilization to the savage wastes of the Mojave.' Hoover Dam was the symbol of the expedition-reports from the Followers of the Apocalypse had confirmed that it was still intact as early as 2170-and its occupation by NCR troops in 2274 was a celebrated event. Even more exciting was the restarting of the dam's hydroelectric plant eleven months later, which dramatically improved the access of many NCR citizens to electricity and water.
    Since then, most of the news has been bad. Skirmishes with local tribes and the first battle for Hoover Dam have cost the lives of more than 400 of the NCR's soldiers and civilians. Until the oft-promised annexation of New Vegas becomes a reality, the government continues to spend much of its budget on 'safeguarding the region' while in return receiving not one Cap in tax revenue. The expedition has proved to be an enduring, low-intensity political embarrassment for President Kimball.
    Among NCR citizens, the most common political attitude is impatience. They want Vegas annexed; they want it over with. Most expect that this will finally occur once Caesar's Legion has been 'beat for good.' Opposition to the Vegas occupation amounts to a vocal minority, and of these, most oppose it as a waste of lives and tax caps. The more radical opinion that the expedition amounts to the imperialist subjugation of an unwilling territory is seen as unpatriotic: the kind of pap spouted by the good-for-nothing agitators like those Followers of the Apocalypse."
    (Fallout: New Vegas Official Game Guide/Behind the Bright Lights & Big City)
  2. 2.0 2.1 2.2 Fallout: New Vegas Official Game Guide Collector's Edition p.372-376: "[3.33] Hoover Dam
    All of the Main Quest in Act III centers around this location, as do the Main Quests involving the visit of President Aaron Kimball. A stronghold of extreme strategic importance for centuries, this location has seen recent turmoil between major Faction too. A few years before current events, Caesar's Legion rolled in, led by ex-Mormon missionary Joshua Graham, Caesar's Legate. Not considering NCR's army to be a serious threat, Graham exercised somewhat lax control over the Legion. During the Battle of Hoover Dam, NCR Rangers and Sharpshooters from First Recon employed risky tactics against the Legion with the help of the enlisted Troopers, and despite horrific loss of life, Caesar's forces were pushed back, but not routed.
    The NCR has been holding the dam continuously since, and have fortified positions along the dam and up and down the west side of the Colorado River. Recently, the Legion pushed the NCR off of the east side of the river at the Battle of Willow Beach (which destroyed an NCR military camp) and the Battle of Arizona Spillway. Day to day military operations at the dam are under the command of Colonel Moore. While troopers are active here, there are also a large number of civilian contractors who are trying to keep the dam running. They are of a secondary concern to Moore, who is preparing from for an impending attack by Caesar and a visit by President Kimball."
    (Fallout: New Vegas Official Game Guide Collector's Edition Tour of the Mojave Wasteland)
  3. Romanes eunt domus in Life of Brian
  4. J.E. Sawyer Formspring


Hoover Dam