Thousands of years ago, the heavens ensured Mistledale's future prosperity when a falling star plowed a hundred mile long, thirty mile wide swath through the elven woods.  The trees never regrew in the scar where the star had fallen, but the land proved amazingly fertile once Dalefolk put it to the plow.  Mistledale has always been the lucky dale - blessed with fertile land, protected from foes such as the Zhentil Keep and Sembia by intervening dales or the Elven Court, and occupying excellent trade routes between larger areas like Cormyr and the Moonseas.
The largest and most densly populated area is the town of Ashabenford, located along the River Ashaba.