Each menu allows you to build any building or track your population. You will want to spend some time working with the menus to become quick and proficient in using all the options available. You do not want to be looking for an option in the heat of battle, so be prepared. One thing I learned the hard way is that if you lose control of the towers that protect your town you lose all the buildings that the tower protects. One of my favorite features is the ability to garrison your towers with additional men, which makes the fortifications easier to defend.
Redundant towers close together are very effective in protecting each other.
This is the area where this game excels. There is so much to talk about, I do not know where to start. Let me hit the highlights and leave the rest to your imagination or playing the game yourself. The buildings built by each race have an authentic look. I liked all three and find it difficult to pick a favorite, but I lean a little more toward the Egyptian since I have always been fascinated with pyramids and the culture.