Heroes of Might and Magic IV
Here
- A Pattern Language for Heroes IV Maps
 - Castles of Annuvin
 - Heroes IV Creature Ratings in PEONs
 - How far away from a town do you need to be to cast Town Gate?
 - How to Create an Unlimited Number of Unique One-Way Portals
 - Ideas for the design of a Heroes IV map
 - Map Sizes
 - Notes on Reverse-Engineering the Heroes 4 Map File Format
 - Scenario Notes
 - The Heroes IV Coordinate System
 - What do extra-large maps put in starting areas?
 - battle-of-the-bards
 
Elsewhere
- maps4heroes.com - A huge collection of high-quality player-made maps. See also my own map archive.
 - heroesofmightandmagic.com - The official website, with descriptions of every hero, creature, spell, artifact, and building.
 - Heroes Community Forums