Since it looks like this has been necro-ed I'll mention that I just published a 300-page sandbox hexcrawl. It's written for OSE but can adapted for different systems pretty easily.
This book combines the Compiled Basilisk Hills cluster with the Supplemental book, creating a hexcrawl region of 107 total 6-mile hexes. Supplemental HexcrawlConsisting of 98 6-mile hexes that surround the main Basilisk Hills cluster, this supplemental book provides enough dungeons, lairs, and...