Master of the Mojave

 is an achievement in Fallout: New Vegas which is awarded for successfully discovering 125 locations.

This can easily be obtained by choosing the Explorer perk when you reach lvl 20 which shows all locations so simply go out and explore!

BUGS: (PS3 Confirmed) Can be given after discovering only 75 locations. This may be due to the in game challenge "Master of the Mojave" that only requires 75 locations to be awarded experience.