This article is considered accurate for the current version (1.58) of the game.
ATrench is a player-made upgradable structure that is dug in the ground with a Shovel and serves as a defensive position for soldiers. There are two trench variants: Trench Connector and Trench Emplacement.
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A dugout that's used for cover and as passageways between Bunkers. Connects to other Trenches and Bunkers.
It can be connected to Bunkers and other trenches to build longer pathways. Trenches can either join up on their ends or in their middle. During placement the trench snaps automatically to existing trenches or bunkers, hold Shift to disable this.
Trenches can be upgraded with several small modifications simultaneously via the structure's upgrade menu. After selecting an option your character will do a short animation (if you have the required materials) and the modification will appear, no hammering required. Modifications can be removed by right clicking on the upgrade option.
Name
Icon
Description
Cost
Removal
Barbed Wire
Slows the enemy infantry attempting to invade this Trench. Each Barbed Wire covers only third the length of the trench on the long side.
1
20
Sandbags
A defensive barrier that hinders enemy movement and provides cover during combat. Each Sandbags covers only third the length of the trench on the long side. Soldiers inside a trench cannot shoot over sandbags and cannot exit from a side that has sandbags.
The original builder can reserve it for a Squad for 52 hours in the upgrade menu to prevent non-members from modifying it, upgrading it, or attaching structures to it. The reservation can be refreshed by any squad member. If the reservation expires, the structure can never be reserved again.
Note that a trench not connected to a Bunker Base can be modified by the enemy even if you've reserved it. Inversely, the enemy can't modify your trench if it's connected to a bunker base even if you didn't reserve it.
Demolition
The original builder, and squad members if reserved, can instantly demolish it if it was built less than 3 hours ago. The materials used in the construction and upgrades are refunded and dropped under the player. Trench blueprints can also be demolished by the builder if under 3 hours old.
Fill In
A tier 1 trench can be filled in with a Shovel, using a button in its upgrade menu, to remove it and restore the landscape around it. It creates a blueprint over the trench which must be dug with a shovel. A Tier 1 Trench husk can also be filled in in the same manner.
Reconstruction
When destroyed, Trenches leave a destroyed version of themselves (a "husk"). They can be rebuilt with the same tool (in Upgrade Mode) and materials used to build the Tier they were on. All previously installed modifications are kept and don't need to be reinstalled.
Use
Defensive Position
It offers great cover and good firing positions for infantry. It is particularly difficult to hit a soldier in a trench with small arms. Trenches are especially useful when linked together in a network to give mobility to the soldiers. It serves to protect infantry against Artillery. It also slowly warms up infantry in it during Snow Storms.
Trenches are neutral structures by default, if an enemy takes your trench, they can use it against you. For this reason care must be taken when digging trenches to avoid accidentally aiding the enemy and hampering one's own team. Both teams are able to upgrade or modify trenches unless they are connected to a Bunker Base, which prevents enemies from adding or removing modifications.
When destroyed, the husk it leaves can still be used by soldiers to hide inside it by crouching but it offers worse cover than a normal trench. Unlike normal trenches, all vehicles can drive over trench husks. The husk also does not protect infantry from Snow Storms.
Network Connection
The Base Upgrades unlocked by a Bunker Base spread through and apply to all connected Trench types and Bunkers, up to a maximum range of 40 pieces. Trench husks also spread Base upgrades.
Resistance
It is very resistant to all damage types except Demolition. It is especially good at withstanding artillery. The destroyed Trench has the same health and resistance but its decay is faster and cannot be prevented.
“
A dugout that's used for cover and as passageways between Bunkers. Connects to other Trenches and Bunkers.
It can be upgraded to Tier 3 with 10 Concrete Materials if it is connected (by bunkers and trenches) to a Bunker Base with the Concrete Structures upgrade. The concrete takes 24 hours to dry, during which the trench is more vulnerable.
Modifications
Trenches can be upgraded with several small modifications simultaneously via the structure's upgrade menu. After selecting an option your character will do a short animation (if you have the required materials) and the modification will appear, no hammering required. Modifications can be removed by right clicking on the upgrade option.
Name
Icon
Description
Cost
Removal
Barbed Wire
Slows the enemy infantry attempting to invade this Trench. Each Barbed Wire covers only third the length of the trench on the long side.
1
20
Sandbags
A defensive barrier that hinders enemy movement and provides cover during combat. Each Sandbags covers only third the length of the trench on the long side. Soldiers inside a trench cannot shoot over sandbags and cannot exit from a side that has sandbags.
The original builder can reserve it for a Squad for 52 hours in the upgrade menu to prevent non-members from modifying it, upgrading it, or attaching structures to it. The reservation can be refreshed by any squad member. If the reservation expires, the structure can never be reserved again.
Note that a trench not connected to a Bunker Base can be modified by the enemy even if you've reserved it. Inversely, the enemy can't modify your trench if it's connected to a bunker base even if you didn't reserve it.
Demolition
The original builder, and squad members if reserved, can instantly demolish it if it was built less than 3 hours ago. The materials used in the construction and upgrades are refunded and dropped under the player.
Fill In
A Tier 2 Trench can be filled in with Basic Materials and an Advanced Construction Vehicle, using a button in its upgrade menu, to remove it and restore the landscape around it. A Tier 2 Trench husk can also be filled in in the same manner.
Reconstruction
When destroyed, Trenches leave a destroyed version of themselves (a "husk"). They can be rebuilt with the same tool and materials used to build the Tier they were on. The previously installed modifications are kept.
Use
Defensive Position
It offers great cover and good firing positions for infantry. It is particularly difficult to hit a soldier in a trench with small arms. Trenches are especially useful when linked together in a network to give mobility to the soldiers. It serves to protect infantry against Artillery. It also slowly warms up infantry in it during Snow Storms.
Trenches are neutral structures by default, if an enemy takes your trench, they can use it against you. For this reason care must be taken when digging trenches to avoid accidentally aiding the enemy and hampering one's own team. Both teams are able to upgrade or modify trenches unless they are connected to a Bunker Base, which prevents enemies from adding or removing modifications.
When destroyed, the husk it leaves can still be used by soldiers to hide inside it by crouching but it offers worse cover than a normal trench. Unlike normal trenches, all vehicles can drive over trench husks. The husk also does not protect infantry from Snow Storms.
Network Connection
The Base Upgrades unlocked by a Bunker Base spread through and apply to all connected Trench types and Bunkers, up to a maximum range of 40 pieces. Trench husks also spread Base upgrades.
Resistance
It is very resistant to all damage types except Demolition. It is especially good at withstanding artillery. Tier 2 has more health than Tier 1. The destroyed Trench has the same health and resistance but its decay is faster and cannot be prevented.
“
A dugout that's used for cover and as passageways between Bunkers. Connects to other Trenches and Bunkers.
„
— In-game description
Construction
A Tier 2 Trench can be upgraded to Tier 3 with a Hammer and 10 Concrete Materials if it is connected (by bunkers and trenches) to a Bunker Base with the Concrete Structures upgrade.
Concrete Settling
It must dry off for 24 hours, however small modifications can be added immediately. The duration increases during Snow Storms and Rain Storms depending on their intensity (up to double with highest intensity).
While very sturdy when dry, it is extra vulnerable while wet. The vulnerability depends on how wet the concrete is and functions as a damage multiplier. Wet concrete that's just been placed has a x10 damage multiplier compared to dry concrete. After 8 hours the damage multiplier is roughly x3, and x2 after 12 hours.
Modifications
Trenches can be upgraded with several small modifications simultaneously via the structure's upgrade menu. After selecting an option your character will do a short animation (if you have the required materials) and the modification will appear, no hammering required. Modifications can be removed by right clicking on the upgrade option.
Name
Icon
Description
Cost
Removal
Barbed Wire
Slows the enemy infantry attempting to invade this Trench. Each Barbed Wire covers only third the length of the trench on the long side.
1
20
Sandbags
A defensive barrier that hinders enemy movement and provides cover during combat. Each Sandbags covers only third the length of the trench on the long side. Soldiers inside a trench cannot shoot over sandbags and cannot exit from a side that has sandbags.
Provides cover against enemies that have entered this Bunker. Only available at Tier 3.
200
20
Reservation
The original builder can reserve it for a Squad for 52 hours in the upgrade menu to prevent non-members from modifying it, upgrading it, or attaching structures to it. The reservation can be refreshed by any squad member. If the reservation expires, the structure can never be reserved again.
Note that a trench not connected to a Bunker Base can be modified by the enemy even if you've reserved it. Inversely, the enemy can't modify your trench if it's connected to a bunker base even if you didn't reserve it.
Demolition
The original builder, and squad members if reserved, can instantly demolish it if it was built less than 3 hours ago. The materials used in the construction and upgrades are refunded and dropped under the player.
Reconstruction
When destroyed, Trenches leave a destroyed version of themselves (a "husk"). They can be rebuilt with the same tool and materials used to build the Tier they were on. The previously installed modifications are kept.
Use
Defensive Position
It offers great cover and good firing positions for infantry. It is particularly difficult to hit a soldier in a trench with small arms. Trenches are especially useful when linked together in a network to give mobility to the soldiers. It serves to protect infantry against Artillery. It also slowly warms up infantry in it during Snow Storms.
Trenches are neutral structures by default, if an enemy takes your trench, they can use it against you. For this reason care must be taken when digging trenches to avoid accidentally aiding the enemy and hampering one's own team. Both teams are able to upgrade or modify trenches unless they are connected to a Bunker Base, which prevents enemies from adding or removing modifications.
When destroyed, the husk it leaves can still be used by soldiers to hide inside it by crouching but it offers worse cover than a normal trench. Unlike normal trenches, all vehicles can drive over trench husks. The husk also does not protect infantry from Snow Storms.
Network Connection
The Base Upgrades unlocked by a Bunker Base spread through and apply to all connected Trench types and Bunkers, up to a maximum range of 40 pieces. Trench husks also spread Base upgrades.
Resistance
It is very resistant to all damage types except Demolition. It is especially good at withstanding artillery. Tier 3 has more health than Tier 2 but takes more damage while its concrete is wet. The destroyed Trench has the same health and resistance but its decay is faster and cannot be prevented.
Gallery
Tier 2 Bunkers and Trenches used in combination
A Trench Blueprint, showing how far away it is from the nearest supply source
for 52 hours in the upgrade menu to prevent non-members from modifying it, upgrading it, or attaching structures to it. The reservation can be refreshed 
by any squad member. If the reservation expires, the structure can never be reserved again.
if it was built less than 3 hours ago. The materials used in the construction and upgrades are refunded and dropped under the player. Trench blueprints can also be demolished by the builder if under 3 hours old.
in its upgrade menu, to remove it and restore the landscape around it. It creates a blueprint over the trench which must be dug with a shovel. A Tier 1 Trench husk can also be filled in in the same manner.
