Fields

Apart from the buildings you will also find fields where you can gather your ressources.

Logging site
The logging site is where you cut trees. This yields wood that can be used as a resource. Wood is used for virtually everything that involves construction. Wood is the base resource of Erectus. Wood is yielded in the forest. The most difficult part of gathering wood is getting the wood to the storehouse as quickly as possible, especially when the logging takes place in deeper parts of the woods. By improving the forests's infrastructure you can increase wood production. A maximum of 10 workers per level can be assigned to logging duties. Wood can be used much more efficiently once the city has a carpentry available to it. The carpentry also increases wood production.

Clay excavation
Clay excavation is situated near the river. The river deposits silt which is an excellent material. The clay is excavated after which it is well suited to use as plaster to reinforce buildings with, making them water and wind resistant. Clay excavation can be expanded upon by excavating a larger area. You can have up to 10 workers per level working at an excavation site. Once a city has a stone masonry available to it it can turn clay into stone which can be stored for later use. Stone is used for more complex constructions such as a city wall. Many buildings will also require stone to upgrade to their higher levels.

Iron mining
Iron ore is a very important but rare resource in Erectus. It's hard to come by and difficult to process but nevertheless makes a big difference in the game. Iron is needed to provide your troops with weapons and protective gear and to reinforce buildings and provide them with locks. Initially, iron ore is found on the surface, mines are built later on though mines can only be built in a city. Villages simply can't afford mines and even if they could, a mine in a village would run too high a risk of getting plundered. A maximum of 10 workers per level can be used to mine for iron ore. Iron is stored in the storehouse and because it's usually stored in small amounts there will always be always be enough space to store iron. As soon as a city has a forge available to it, melting ore will be much faster and iron production will greatly increase.

Farm
Everything in Erectus will rise and fall in accordance with the food production. Only when there's a surplus of at least 50 food per hour can you expand your civilization by building a house. Your civilization is important; they have to work, serve in the army and generate tax revenues. A maximum of 10 farmers per level can be working on a farm at once. In a city the farm can be upgraded to a maximum of level 30, a farm in a village can be upgraded to a maximum of level 15. Should a city have a bakery, butcher, or greengrocer available to it the food production will increase exponentially. The food will be processed and distributed much more evenly and the added production bonus can go as high as 75%.