Bridge

Bridges are structures that can be built on water, and allow light buildings on top of them.

Acquisition

Building a bridge requires 12 Wood and 1,500 ticks (25 secs) of work. They can only be constructed on the following terrain types:

Summary

While structures, bridges act similar to a floor tile. Unlike the water its on, bridges don't penalize movement, making travel faster. They can also support structures that require a terrain affordance of "light", such as wooden walls and buildings, but not structures that require medium or heavy terrain affordance, like any other type of wall. The terrain types that allow bridges do not allow floors, so bridges are the only way (short of a moisture pump) to improve the movement speed, cleanliness and beauty of such tiles, or enable them to count as "floored" for the bedroom and throne room needs of a pawn with a noble title.

Bridges can be damaged or destroyed by fire or explosions.^{[Specificity]} When destroyed, whatever is built on top will be destroyed alongside it.

Bridges can also be removed from the "Remove Bridge" gizmo under Architect/Structures.

Analysis

Bridges are essential if you need certain objects on water, marsh or mud, such as wooden walls. They are required to build moisture pumps over water, which can eventually remove the water. And due to the faster move speed, you can speed up colonists by placing bridges through their path. Raiders can also path through the bridge, giving you some control over their movement.

In practice, raiders will not attack any wall or door unless 1. they are sappers or breachers, or 2. they have no reasonable target to access to without breaking a wall. Therefore, wooden walls are relatively safe to use. For example, bridges and walls can be used to surround your watermill generators, making them almost non-targets for raiders.

Power conduits can be built on bridges, replacing the need for waterproof conduits. The latter costs 10 steel, which is 10x more than a regular conduit. However, the bridge has its own wood cost, and bridges are much more vulnerable to fire.

Path baiting

Because bridges have a significantly lower pathcost compared to water and mud, raiders will naturally prefer to path over most bridges but will also not attract attacks from breachers like walls used to constrict passages. This can be exploited by placing traps on the bridges for raiders to trigger. While spike traps will work for this purpose, IED traps are particularly effective especially when paired with a large roof supported by a wooden wall that will be destroyed by the IED's detonation, dropping the roof on the enemies for additional damage.

This strategy works even if the bridge does not cross the entire span of the water, as even the small improvement in path cost is often enough to tempt raiders to use them.

Version history

1.2.2753 - Can now be auto-rebuilt.

Architect

Structure: Animal flap • Autodoor • Bridge • Column • Door • Fence • Fence gate • Ornate door • Wall • Security door
Related: Roof