City Defenses
Tunnels
Some cities may require secret entrances and exits, usually for puposes of supporting defensive warfare. They are often placed to provide access to a point beyond where atacking forces would be located.
Since cities may have tunnels of widely varying length (depending on terrain and military needs), their cost is now going to vary by the length of the tunnel constructed. Cost tables will be available for creating a tunnel of 100', but actual costs will vary based on the length needed.
The level of tunnel describes its space, construction, and quality. Tunnel entrances at both ends are always well-concealed. They are assumed to be tunneling through compacted soil rather than rock, mud, or sand and avoid any underground defensive outworks that may be present.
Tunnels may be upgraded, but (at least starting after level 3.0) portions of the previous tunnel will need to be removed in order to increase the tunnel size and materials. Therefore, the rules and costs for upgrading walls in place will also be used for upgrading tunnel levels.
| Level | Type | Description |
|---|---|---|
| 1.0 | Crawlspace | Only about 3' wide and tall, this is only fit to be crawled through, on hands and knees at best. Raw dirt walls and ceiling are very unstable and prone to collapse in the vicinity of any disturbance. External water seepage from nearby sources or weather is also likely to be a problem over time. Maintenance costs are high. |
| 2.0 | Very narrow | A walkway, of sorts, about 3'-4' wide and 5'-6' tall. Passage by average-sized men without bulky armor is possible while standing or stooping, often with their shoulders brushing against the walls. Dirt walls and ceilings are packed down into a rough but semi-stable surface, but damage to it should be avoided. External water seepage is still a potential problem. Maintenance costs are relatively high. |
| 3.0 | Narrow, finished | A passageway about 5' wide with an arched roof over 6' tall for stability. Walls and ceiling are packed earth covered by smooth dried-mud surfaces to improve damage resistance. Better resistance to water seepage in small amounts. Maintenance costs are reasonable. |
| 4.0 | Reinforced | A smooth-finished passage about 10' wide and 7' tall. Partially embedded into the walls and ceiling are wooden pillars with reinforcing cross-beams for better support against collapse with normal usage. |
| 5.0 | Surfaced | About 15' wide and 10' tall, the ceiling in a tunnel of this sort is covered by wooden planks and is supported by frequent wooden side pillars. Walls are mostly covered by thin, rough flagstones, mortered in place with mud compounds as non-load-bearing surface protection. The floor is dry-laid flagstone. |
| 6.0 | Brick | A well-constructed passage about 20' wide using fired and mortered bricks for floor, ceiling, and walls. Brick side-pillars are used to support the ceiling. |
| 7.0 | Stone | A large passageway about 30' wide and 10' tall made entirely of stone masonry. Support pillars on the sides and along the center with small cross-supports help support the ceiling. Occasional hand-operated ventilation may be arranged to support a force moving through the tunnel. |
| 8.0 | Galleries | A large stone passageway, as above, with the addition of occasional side galleries to support extra men in specific areas (such as near either end for better grouping of troops). Mechanically-assisted ventilation is needed, at least on each end and at least while occupied. |
| 9.0 | Double-wide | A stone passageway 50' wide but with a 5' thick supporting wall down the center dividing the tunnel in two. Frequent openings in the wall allow easy passage between the two sides of the tunnel. Side galleries are present fairly regularly and can be used for temporary occupation or long-term storage of supplies. Exterior ventilation with mechanical assistance is necessary with sources all along the length, and such connections to the surface are carefully concealed and protected. |
| 10.0 | Bunkers | As above, but with large living and working areas added frequently alongside the passageway, often cross-connected to one another. Can be used as a long-term place of refuge if adequately stocked with supplies and the endpoints are sufficiently hidden and protected to prevent detection and entry. Alternate concealed exits may be provided at either end or along the length if appropriate. Special venting considerations are taken to allow cooking or work fires that need to be exhausted without allowing smoke to be detected above-ground. |