All the places I know of, that I remember:
Fort Abandon: a rundown NCR fort and a central
location in the game. The railway has a crossroads
here, and if the player so chooses, he can slowly
upgrade the fort into a center of prosperity.
Jericho: Formerly the Jericho Desalination Plant of
New Canaan, Jericho is all that is left of the Mormon
city. The town's prosperity revolves around the fresh
water the still-working plant produces. However, the
plant is old and inefficient, and Jericho is a long
way from being the economic powerhouse it wants to be.
Hoover Dam: The largest city in the game and the
headquarters of the NCR government. The town is built
along the top and sides of the dam. Unfortunately,
Governor Dodge is a weak leader, and the ongoing war
with the Brotherhood of Steel hasn't helped his
popularity much. Still, he's determined to hold the
NCR together after the destruction of Shady Sands by
the Enclave.
Maxson Bunker: A small outpost of the Brotherhood of
Steel. The Brotherhood has become a shadow of its
former self. No longer the sole custodian of advanced
technology in the wasteland, the Brotherhood is
struggling to find a new identity. The current
leadership favors a return to power by wresting all
advanced tech from the hands of "lesser people" by any
means necessary. This attitude hasn't won them any
friends, and because many in the Brotherhood disagree
with such brutal methods, the whole organization is on
the verge of civil war.
Grand Canyon: Due to uranium demand shortly before The
War, the U.S. government removed the GC's status as a
national park and allowed private mining companies to
exploit the GC's supply of uranium (yes, there really
is uranium in the GC). The resulting mess was an
environmental disaster. As a result, the Canyon has
become one of the deadliest places in the wasteland,
home to hideous mutant things seen nowhere else. Sane
people avoid it; too bad The Prisoner will probably
find himself in the deepest, darkest depths of the
Canyon at some point...
Mesa Verde: A small cliff dwelling set high in the
side of a mesa. The people there, called the Ciphers,
seem like any other group of tribals. In reality,
they're quite skilled in science. They hold onto their
secret knowledge in preparation for the day they are
once again worthy to use it. The schematics for many a
forgotten device is painted all over the village
walls, but the few travelers that visit the village
are unaware of the significance, dismissing the
scribblings as "tribal art".
Oroborus: Home to Hecate, a tribal madwoman who sees
herself as a goddess and a prophet. The Daughters of
Hecate are her prime servants, spreading Hecate's will
to all the tribes. The Vipers, Raider exiles from the
West, have become Hecate's fanatical army and crush
anyone who challenges her. The other tribes fear
Hecate's power, and rightly so.
The Nursery: The last hope of the wasteland, where
seeds and another genetic information, preserved from
the world before The War, have been stored. This
hidden valley is a lush, verdant place. Harold the
Ghoul has found his way here, but thanks to the tree
in his head, has been marked as an "interesting
specimen" and has been prevented from leaving by the
Nursery's security bots.
The Twin Mothers: As tribal as tribals get, that's
these guys. They do well for themselves, having skill
in agriculture. They're the descendants of Vault 31,
and their village is built on top of the Vault. The
Vault itself has ceased working long ago, but it's
still a holy place to the Twin Mothers. Hecate has a
powerful influence here, but the tribe hasn't
completely fallen under her sway.
Hangdog Village: More tribals, but these guys are all
about dogs: pets, food, guards, etc. The Hangdogs are
slavers and scavengers, and are often in league with
Hecate. However, they're not all bad and they just
might not try to enslave The Prisoner if he proves
he's good enough to be one of them.
Boulder Dome: A research outpost, filled with all
sorts of scientific equipment. A ZAX supercomputer is
here, but it's been damaged and is unable to run at
full power. Still, the few scientists here seem to
make do, though they're somewhat tightlipped about
what exactly they're working on.
Denver: A ruined city of dogs and skyscrapers. There
is no real civilization here, just a series of
salvager camps set up high in the skyscaper ruins,
away from the endless pack of feral dogs which roam
the streets below.
Burham Springs: A fiery hellhole, thanks to the
ever-burning coal in the mines. Naturally, there's
*something* The Prisoner needs which can only be found
here. Heh.
The Reservation: A ghoul town, and naturally highly
radioactive. The ghouls are sick of being the
underdogs of the wasteland, and they have a new leader
who's going to stick it to the humans good. Firing
radioactive artillery shells via Nuclear Nellie, the
ghouls' bigass gun, into every town ought to clear
those pesky humans out. Of course, Nellie isn't quite
working right and the ghouls haven't figured out a way
to move Nellie around easily.
Bloomfield Airbase: An old Airforce base, littered
with the rusting carcasses of numerous air vehicles.
It's also got not one but TWO working shuttles. Anyone
up for a trip into space?
B.O.M.B. 001: The Ballistic Orbital Missile Base and
the U.S.'s far more destructive version of Sputnik.
It's the endgame area, and won't be seen until the end
of Act 3.