Buildings

Every building with a use

Regular, normal Building (House, school, shop, ect)
These can provide shelter for people. The earliest houses were made well back in time, in the period of the first humans. It didn't do much, but it helped resist the cold and rain.

Farm
These give food for people, and can be in different types. They can consist of Animals and Crops to feed people, or to sell, for trading or stuff.

Mines
The earliest of the mines were really small, and gave common ores, such as Iron, that seemed to be rare and valuable at the time. If you had one of these, you would be off to a great start!

Not-so Factories
These are not modern factories with the modern day requirements, they just have men who work to create weapons, such as shields, for the military. These were often bigger than a Regular building.

Castle
These would be for a kingdom, if you chose the route of a monarchy, what most would be forced to do. You would require one of these for your leader and lords to stay in, and make all of the important choices in.

Port
These would be at the coast, with boats being located nearby somewhere. They are either used for Traveling, Exploring, Colonizing, Trading or War purposes.

Factories
These are the types that produce Guns and other stuff, such as tanks and artillery weapons. They have the same circumstances as the "Not-so Factories", but they would use fuels, such as coal.

Airports
Airports would usually be one of the "rarer" things for a tier 4 nation to have, as planes are used for more modern circumstances. Normally, in this time, you would use these to your advantage, and you would bomb places, attack enemy men or just fight enemy men.

Research Stations
These would research anything to improve the tech, military or way the people live. Mostly, they would benefit you, but if you do the wrong move, it would benefit your enemies.

Nuclear Silo/Base
These both consist of nukes, and other nuclear weapons that do brutal damage to enemies. They are required to make a nuke.