In Heroes of Might and Magic III, scenario maps are built on square grid dimensions. Tile dimensions for standard map sizes (S: 36×36, M: 72×72, L: 108×108, XL: 144×144) and HotA expanded sizes (H: 180×180, XH: 216×216, G: 252×252) are read directly from the map files on this site by our binary parser (scrapers/h3m/h3m.py). HotA expanded formats are additionally documented in the official Horn of the Abyss documentation.
Complete Map Sizes Reference Table
| Code | Name | Dimensions | Tiles / Layer | Added In | Underground Layer | Archive Maps | Browse Category |
|---|---|---|---|---|---|---|---|
| S | Small | 36×36 | 1,296 | The Restoration of Erathia (1999) | 36×36 (up to 2,592 tiles total) | 1,074 | Small Maps » |
| M | Medium | 72×72 | 5,184 | The Restoration of Erathia (1999) | 72×72 (up to 10,368 tiles total) | 2,448 | Medium Maps » |
| L | Large | 108×108 | 11,664 | The Restoration of Erathia (1999) | 108×108 (up to 23,328 tiles total) | 1,854 | Large Maps » |
| XL | Extra Large | 144×144 | 20,736 | The Restoration of Erathia (1999) | 144×144 (up to 41,472 tiles total) | 2,932 | Extra Large Maps » |
| H | Huge | 180×180 | 32,400 | Horn of the Abyss (HotA 1.3.0) | 180×180 (up to 64,800 tiles total) | 89 (Part of Huge collection (89 maps)) | Huge Maps Collection » |
| XH | Extra Huge | 216×216 | 46,656 | Horn of the Abyss (HotA 1.3.0) | 216×216 (up to 93,312 tiles total) | 89 (Part of Huge collection (89 maps)) | Huge Maps Collection » |
| G | Giant | 252×252 | 63,504 | Horn of the Abyss (HotA 1.5.0) | 252×252 (up to 127,008 tiles total) | 89 (Part of Huge collection (89 maps)) | Huge Maps Collection » |
How Underground Levels Work
Every scenario map in Heroes of Might and Magic III supports an optional two-level layout: a Surface layer and an Underground subterranean layer.
- Identical Dimensions: When an underground level is present, it possesses the identical grid dimensions as the surface level (for instance, a 144×144 XL map has a 144×144 surface and a 144×144 underground).
- Double Playable Area: Enabling subterranean terrain doubles the total tile count of the scenario (up to 127,008 total tiles on a 252×252 Giant map).
- Subterranean Gates: Movement between the surface and underground layers requires subterranean gates or specialized spells (such as Dimension Door or Town Portal with advanced Earth Magic).
Historical Origins: RoE vs. HotA
The base game The Restoration of Erathia (1999) supported four map sizes (S, M, L, and XL) up to 144×144 tiles. This limit persisted through the official expansions Armageddon’s Blade and The Shadow of Death.
The Horn of the Abyss (HotA) expansion extended the engine’s internal limits:
- HotA 1.3.0: Added support for H (180×180) and XH (216×216) map sizes.
- HotA 1.5.0: Added support for the G (252×252, Giant) map size, currently the largest playable scenario size in the game.
Sources & Citations
- Map files on this site: Scenario tile dimensions and sizes are read directly from binary
.h3mheaders by our parser (scrapers/h3m/h3m.py,SIZE_LABELS). - Horn of the Abyss Official Documentation ↗ (read October 18, 2026): “Added support of new map sizes: H (180x180), XH (216x216), G (252x252).”