Terrain -> Introduction
Victory will go to those whom best understand and utilize terrain to their advantage, for example, by occupying benefitial terrain, or forcing the enemy to fight from poor terrain. When exploited properly, terrain also can be used to help corner, outflank, or surround your enemies.
 

Terrain -> Cities
It is important to understand the basics of city terrain in Axis and Allies RTS. Simply put, it's good for infantry, and bad for vehicles. While in city terrain, the city terrain modifier can be seen in the information panel
 

	MAXIMUM SPEED ADJUSTMENT	DEFENSE VALUE BONUS	ARMOR PIERCING RESISTANCE	GUNFIRE RESISTANCE
INFANTRY	2.0	+4	+20%	N/A
VEHICLES	3.0	N/A	N/A	-20%

BAD

GOOD

As you can see, infantry receives a huge defense value bonus as well as an additional 20% resistance to armor piercing (AP) attacks. Infantry already has a base resistance of 20% to AP attacks, giving Infantry at total of 40% AP resistance while in city terrain.
 
The defense value bonus will help infantry survive special op bombs... Most experienced players will wait to bomb infantry, until they are outside of city, jungle, or forested areas.
 
Vehicles have a base resistance of 40% to Gunfire attacks, so they still possess a 20% Gunfire resistance while in city terrain. The speed penalty by itself is not huge, as most mechanized regiments being produced online will have tank destroyers in them [AT-Mech] which have a max speed of 3.5. A regiment can only move as fast as it's slowest unit.
 
The biggest problem vehicles face in city terrain is retreating. City streets can become very congested, and units/regiments easily get tangled with each other, making retreating your regiments more difficult. Use of the single retreat is nearly impossible as regiments often cannot get past the friendly and enemy forces around them.
 
There will be times you have to enter a city with vehicles, just do so with care. Make sure you leave yourself a clear path of retreat, and don't let enemy forces flank you, and block your avenue of escape. If your vehicles rout within the city they will likely be killed.
 
Cities are covered in detail in our Guide:
City Control and Strategy _[1][2][3]

Terrain -> Jungle
Very similar to city and forest terrain, as far as it's effect on different units; and once again, it's good for infantry, and bad for vehicles. Vehicles move extremely slow (slower than any other terrain) in the jungle. While in jungle terrain, the jungle terrain modifier can be seen in the information panel
 

	MAXIMUM SPEED ADJUSTMENT	DEFENSE VALUE BONUS	ARMOR PIERCING RESISTANCE	GUNFIRE RESISTANCE
INFANTRY	2.0	+4	+20%	N/A
VEHICLES	1.5	N/A	N/A	-20%

BAD

GOOD

In the jungle, infantry receives the same defense value bonus and 20% resistance to armor piercing (AP) attacks as in city and forest terrain. Infantry already has a base resistance of 20% to AP attacks, giving Infantry at total of 40% AP resistance while in jungle terrain.
 
The defense value bonus will help infantry survive special op bombs... Most experienced players will wait to bomb infantry, until they are outside of city, jungle, or forested areas.
 
Infantry can actually outrun vehicles while in the jungle, making the Philippines a favorite map of infantry lovers.
 
Vehicles have a base resistance of 40% to Gunfire attacks, so they still possess a 20% Gunfire resistance while in jungle terrain.
 
The biggest problem vehicles face in jungle terrain is how long it takes to retreat due to the speed penalty. It takes regiments so much longer to retreat, that it is easy to retreat them too late and end up getting them killed. Just be aware, and retreat vehicles sooner than you would in any other terrain.
 
If you are playing a jungle map, you will likely have to enter the jungle with vehicles, just be careful. Make sure you leave yourself a clear path of retreat, and don't let enemy forces flank you, and block your avenue of escape. If your vehicles rout within the jungle they will likely be killed.

Terrain -> Forest
Forests are present on most maps (except for Philippines and North Africa), and how dense they are depends on the map played and game settings. The more forest there is on a map, the more infantry you will likely see. Very similar to city and jungle terrain, as far as it's effect on different units; and once again, it's good for infantry, and bad for vehicles. While in forest terrain, the forest terrain modifier can be seen in the information panel
 

	MAXIMUM SPEED ADJUSTMENT	DEFENSE VALUE BONUS	ARMOR PIERCING RESISTANCE	GUNFIRE RESISTANCE
INFANTRY	2.5	+4	+20%	N/A
VEHICLES	2.0	N/A	N/A	-20%

BAD

GOOD

In the forest, infantry receives the same defense value bonus and 20% resistance to armor piercing (AP) attacks as in city and jungle terrain. Infantry already has a base resistance of 20% to AP attacks, giving Infantry at total of 40% AP resistance while in the forest.
 
The defense value bonus will help infantry survive special op bombs... Most experienced players will wait to bomb infantry, until they are outside of city, jungle, or forested areas.
 
Infantry can actually outrun vehicles while in the forest, and have a higher max speed when compared to city or jungle terrain. This helps make forested areas THE hotspot for infantry combat.
 
Enemy infantry will do everything they can to force the battle to the forests, so do what YOU can to deny them that advantage! Even if it means taking an longer route, or attacking their supply lines to force them to retreat (to terrain more favorable to vehicles).
 
If fighting enemy vehicles in the forest, try and make sure both of you and your opponent are in the forest, or even better, just your opponent.

Terrain -> Sand
The sand modifier has little effect, capping just the speed of both infantry and vehicles. In sand, the advantage would go to vehicles, since infantry receives no bonuses and should be trying to fight in city, jungle, and forested areas.. While in sand, the sand terrain modifier can be seen in the information panel
 

	MAXIMUM SPEED ADJUSTMENT	DEFENSE VALUE BONUS	ARMOR PIERCING RESISTANCE	GUNFIRE RESISTANCE
INFANTRY	2.0	N/A	N/A	N/A
VEHICLES	3.5	N/A	N/A	N/A

BAD

GOOD

Infantry has a hard time competing with vehicles in sand, since it receives no bonuses and is also vulnerable to special op bombs while "out in the open". Only enter sandy areas if it offers some sort of reward, such as killing enemy regiments or destroying enemy bases. Don't group too many regiments together while in sand, as you may be "bombed"
 
Although vehicles do suffer a speed penalty in sand, it's better to be fighting there than in city, jungle, or forest terrain.

Terrain -> Snow
Snow maps are not played that often, mostly because you cannot read the message log (white text) to keep informed of important game events, with snow in the background.. That being said, the snow modifier has little effect, capping the speed of both infantry and vehicles. In snow, the advantage would go to vehicles, since the speed penalty makes any type of infantry rush somewhat difficult.
 

	MAXIMUM SPEED ADJUSTMENT	DEFENSE VALUE BONUS	ARMOR PIERCING RESISTANCE	GUNFIRE RESISTANCE
INFANTRY	2.0	N/A	N/A	N/A
VEHICLES	3.5	N/A	N/A	N/A

BAD

GOOD

Unless it is a small map, you might avoid any large scale infantry attacks on a snow map. The max speed penalty might mean your opponent has mech out, by the time you get to his base.
 
No huge deal here, better to be in the snow, than in forest, city, or jungle terrain.

Terrain -> Proper Use

What follows are some basic examples of how to use terrain to your advantage using different types of units. The basic idea will always be: Fight from beneficial terrain, force your opponents into poor terrain, or hopefully both!
 
Try and position your troops right on the edge of benefitial terrain such as city, forest, and jungle, so that enemy forces will be denied the bonuses those terrains offer. Also, entrenching right on the edge of benefitial terrain is great for holding a key location, but is a defensive tactic only.
 
As always, you will still want to keep your infantry fighting in benefitial terrain such as city, forest, and jungle. However, versus vehicles you will want to retreat back from the edge of these terrains, to force attacking vehicles to fight from inside poor terrain (city, forest, and jungle).
 
Try and put poor terrain such as city, forest, and jungle in-between your vehicles and advancing enemy vehicles. If they are going to attack make them fight with a penalty while you have none. This can be useful to buy time if you are outnumbered, and in such cases entrenchment may be a good idea as well.
 
Also be aware that your opponents may try to do the same to you, much better to take the long way around if the terrain ahead is too dangerous.

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