Block Hex

Block hexes are standardised map units with a diameter of 145 yards, primarily used in city mapping, siege scenarios and tactical engagements over an area too large for a typical 5-foot combat hex battlemap. The distance allows for archery and siege units to fire into adjacent hexes or to join combat within hexes, where they can be settled using large unit combat resolution.

This size of hex provides a structured method for sketching out the general layout of a town or city without requiring the placement of every individual building. Rather than mapping structures one by one, these hexes allow for the broad organisation of urban space, distinguishing between different districts, their purposes, and their relationships to one another. The arrangement of hexes determines the flow of movement, access to resources, and the overall structure of a settlement, shaping how inhabitants interact with their environment. Major features such as roads, rivers, walls, and marketplaces emerge naturally as the city takes form, guiding expansion and influencing the placement of residential, commercial, and civic spaces.

A city mapped with block hexes balances precision and flexibility, providing enough detail to define its major elements while leaving room for natural variation. The placement of hexes defines the density of development, the availability of open space, and the structure of key infrastructure, but it does not dictate the exact arrangement of streets or individual buildings. This approach allows for strategic planning at a city-wide scale while preserving the organic feel of historical or fantasy settlements. Whether a town is tightly packed within defensive walls, sprawled along a riverfront or arranged in orderly districts, the use of block hexes provides a framework that supports both structured design as the city develops.

Block Types

In a dense urban core, this is sufficient space to fit approximately 80 to 90 townhouse like structures, with narrow streets, so approximately one neighbourhood. Workshops and other buildings that require yards, storage space or addition workspace beyond the living space of the family, would equal four such townhouses in size; this would mean that a block hex attributed to a guild would have about 20 to 25 such buildings. Mills, with necessary clearance for the presence of water, wheel, housing, sluiceways and storage, would be three times greater in size than a workshop, and therefore block hex would house 6 to 8 such arrangements.

A public square could range from one-quarter to an entire block hex, depending on its purpose and the layout of the surrounding city. A smaller square taking up about one-quarter of a hex would be a simple open space, perhaps centered around a well, a shrine or a small market with just enough room for daily gatherings. A larger square, occupying half or the entirety of a block hex, would be a major civic space — used for markets, festivals, public speeches or military mustering. If a full hex were dedicated to a grand plaza, it would likely be surrounded by important buildings such as a town hall, a temple or merchant stalls, creating a focal point in the city. The fewer structures placed within the hex, the more open space is left for pedestrian movement, carts or designated assembly areas. Such buildings would take up additional adjoining hexes, with marginal spaces again filled with townhouses or mansions of various size.

Fortifications

Citadels, castles, and fortresses might fill up one or more block hexes, depending on their size and function within a city. A small citadel — a fortified stronghold designed to protect government officials, military leaders or ruling authorities — might occupy a single hex, containing a central keep, barracks, and a small courtyard enclosed by defensive walls. A larger castle, particularly one designed for both residence and military defense, would spread across multiple hexes, incorporating gatehouses, inner and outer baileys, stables, armouries and training yards, as well as halls for governance and ceremony.

A fortress, constructed with purely military intent, might be even larger, prioritising walls, bastions, and defensive structures over residential or administrative spaces. These structures would often be positioned at key strategic points within a city, such as along walls, overlooking harbours or at major crossroads, ensuring that their placement reinforces the city's defenses. Unlike civilian buildings, fortifications demand wide clearance, access to supplies, and strategic sightlines, making their placement within block hexes a defining element of the city's overall layout.

In cases where fortifications extend beyond the city itself, a block hex could also represent a walled perimeter, a detached outpost or a fortified gatehouse, each contributing to the settlement's larger defensive strategy. The number of hexes a fortification consumes is dictated by its complexity, whether it functions as a compact citadel, a sprawling fortress or an integrated castle-palace serving as both a stronghold and a seat of power.

Fairgrounds

Fairgrounds or jousting fields require significant open space, often occupying one or more block hexes, depending on their function and scale. A small tournament ground with a single jousting lane and modest spectator seating could fit within a single hex, allowing space for contestants, officials, and gathered nobles while maintaining enough clearance for safe movement. A larger jousting field, accommodating multiple lanes, grandstands, and tents for knights and their attendants, would likely extend across two or more hexes, particularly if hosting festivals, feasts or large-scale competitions.

A fairground, with its mix of stalls, performance areas, livestock enclosures, and public gathering spaces, requires an even greater footprint. A modest market fair, consisting of merchants, food vendors, and small games, could fit within half a block hex, often positioned alongside a town square or adjacent to a major roadway. A major festival ground, however, could spread across multiple hexes, incorporating open fields, grandstands, race tracks, livestock pens, and temporary pavilions, especially if it is meant to accommodate thousands of visitors or host significant annual events.

The placement of these spaces is critical to city planning, as fairgrounds and jousting fields require access to major roads, accommodations for travelers, and nearby markets or inns to support those attending the event. Whether positioned within city walls as a noble gathering place or outside the settlement where space is more abundant, these areas serve as hubs of activity, shaping the cultural and economic life of the city.

Military Maps

A block hex tactical map provides a structured framework for designing the battlefield around a besieged city, allowing for clear spatial organisation while maintaining flexibility in play. Each block hex defines a specific area of terrain, fortifications or siege activity, ensuring that movement, engagement and positioning remain manageable at a tactical level.

The settlement itself is divided into block hexes, outlining key districts, walls, gates and major streets. Defensive structures, such as outposts, palisades or secondary walls, each occupy their own hexes, layering protection around the city and creating staging points for combat. Gates, bridges and rivers determine access points, with each placed within a hex to influence movement and engagement.

Attacker encampments and siegeworks are distributed in their own hexes, with the main siege camp positioned outside of effective missile range, often spanning multiple hexes if the force is large. Advanced siege positions, including trenches, trebuchet emplacements and battering ram staging areas, move closer to the city, creeping hex by hex as the siege progresses. Stockpiles, command posts and support camps are placed further back, controlling logistics within the siege network.

The surrounding natural terrain is also structured by block hexes, influencing the battlefield. Open field hexes allow easy movement but expose forces to missile fire. Forested hexes provide cover and opportunities for ambush. Hills, marshes and river hexes create obstacles that impact strategic positioning. Road and bridge hexes define access routes, controlling reinforcements or supply lines. If reinforcements are expected, their likely arrival path is assigned a road hex, dictating their approach to the battle.

Sub-blocks

With each block hex dividing into nine sub-blocks, where seven central hexes fit neatly and the six corner diamonds combine with adjacent hexes to form full hexes, each sub-block measures 48 yards across. This subdivision allows for finer tactical detail within a block hex, making it possible to represent smaller-scale engagements, troop movements or structures with greater precision. Each sub-block hex is slightly larger than a Squad Leader hex, which measures 44 yards across. This means that tactical movement, line-of-sight considerations and positioning within a single block hex can be handled in a manner similar to traditional squad-level wargames. The structure also ensures that individual buildings, fortifications, siege works or other battlefield features can be mapped with increased granularity, while still maintaining the broader strategic clarity that block hexes provide.

This subdivision also means that multiple engagements can be resolved within a single block hex, as the smaller hexes allow for finer unit placement. It creates an effective transition between regional-scale mapping and small-unit tactics, ensuring that battles remain both organised and fluid without requiring overwhelming detail at larger scales.

With each sub-block being approximately 145 feet (48 yards) wide and a standard D&D battle map using 5-foot combat hexes, a full-scale battle map within a single sub-block hex would be 29 combat hexes across. This makes the transition from large-scale tactical movement to individual skirmishes seamless, allowing for smooth scaling between regional strategy, unit-based combat and personal encounters.

This system allows a block hex to be used for high-level strategic planning, while individual sub-block hexes provide a detailed framework for resolving unit-based engagements. When combat narrows down even further, a single sub-block hex can expand into a full battle grid, accurately accommodating individual movement, formations and terrain interactions.

Because a block hex divides cleanly into 9 sub-blocks and each sub-block conveniently holds a D&D-scale battlefield, this means that zooming in from a full 2x2-mile tactical map all the way down to individual combat encounters is not only possible but highly structured. The nested scaling ensures that a DM can fluidly move between army movements, squad engagements and personal fights without breaking immersion, making this an ideal system for sieges, large battles or military campaigns where encounters shift between strategic and personal combat.

Computer Modelling

A computer system to manage unit locations and automatically generate visual battlemaps for precise resolutions would make this system efficient and practical. The ability to track movements across block hexes, shift to sub-block tactical engagements and then seamlessly render an individual battle map for unit skirmishes or personal combat would eliminate the need for manual recalculations and redrawing. With a properly designed interface, the system could:

• Track and display unit positions at the block hex level, ensuring that large-scale strategic movements remain clear.

• Dynamically zoom into sub-block hexes, resolving battles at the squad or formation level while maintaining alignment with the larger map.

• Automatically generate a 29-hex-wide battle map when combat needs to be resolved at the individual level, populating it with terrain, fortifications and unit positions based on the broader tactical map.

• Handle real-time adjustments, so that changes at one level (e.g., a city wall breach or a retreating force) update seamlessly across all layers of the map.

• Store and recall unit history, allowing for fog of war, tracking of casualties or reinforcement logistics without manual input.

• Integrate dice rolls and combat resolution mechanics, applying D&D rules or a customised tactical system as needed.

This approach would transform sieges, city battles and large-scale warfare into a fluid, manageable and visually intuitive experience. With procedural generation for buildings, streets and natural features, a DM could instantly generate an appropriate battlefield rather than needing to prepare individual maps in advance. It would also streamline battle resolution, allowing players to shift between the macro- and micro-levels without breaking immersion.

See also,
Land Hex
Village Hex