You will not get in until you finish Waters of Life quest, at the very end of the quest you escort Dr Li through Taft Tunnel and she then leads you into the Citadel. Once you have entered your free to come and go as you please.
if you go to the Jefferson memorial it is right across the river to the right.
Complete the quest "The Waters of Life" to gain access.
after you beat the quest waters of life in the main story line you are introduced in the citadel
Yes you can leave it at any time and fast travel back.
In a bunker at hidden valley in fallout new vegas and in the citadel in fallout 3 or in the capital city area
A giant taco appears and eats you!
scribe rothchild is in the citadel in the b ring or a ring. (not sure)
in the citadel but you can only get in after completing the quest with your dad
you have to complete the quest (The Waters of Life) to get access to the Citadel. http://fallout.wikia.com/wiki/Portal:Fallout_3
The Paladin Gunny wanders around the Citadel, however after you get permission from Elder Lyons for Armour training you will find him in the training area of the Citadel Courtyard.
In certain main building and in the library behind the citadel if you look well enough.
You can hire Jericho and Megaton. Star Paladin in the Citadel Sydney in the National Archives Fawkes Clover in Paradise Falls
no
you first meet them on your way to the GNR station, after that you can find them at the citadel
Scribe Jameson can be found wandering around the Library or Archives in the A Ring, look out for her distinctive red scribe uniform.
After you get to the citadel after you can talk to elder lions and he will tell you where to go and you can get it