So when I was working on the mission with the Great Khans.....I was trying to get some of the members to talk against Papa Khan....during this(I am not sure when) For some reason Hoover Dam is off my map! I can still go there but I cannot fast travel there. The location does not show up on my pip boy.

Someone PLEASE HELP!

Can you load a previous save? Never heard of anyone with this issue before. Are you sure you had the hoover dam map icon?