I created a 3x5 card sandbox and have spent the afternoon fleshing out what's become Dornwald!
It totals 66 hexes (6Hx11W) and now I am finishing out the tables, history and setting.
Unlike Blackmarsh with lots of great pre-determined encounters, Dornwald is more of a search and find setting. There are 2 keyed locations...but the rest of it is determined randomly through searching...or could be predetermined by a referee using the charts.
One could just create a party and search it solo even! It's an outline with enough information to get you started and playing, but not so detailed that every last coin and treasure is pre-determined. Some dislike that--but I prefer it as it allows individual tailoring and involves the Referee in defining the play space.