Princes of the Apocalypse
Map of Faerun
Below is a link to a rather more political map of Faerun. The area in which our tale takes place is the Sword Coast area; Northwest, with Waterdeep being the largest nearby city.
Based on the race of your character and the story however, feel free to have your character hail from anywhere in Faerun…you just need a reason to be in Red Larch