The Basics

The Network Addon Mod (NAM) is designed to pave the way to new horizons in Sim City 4, quite literally. There are so many network options in this single mod that learning them can feel off-putting and overwhelming. Frankly, very few players will ever need all of them there's that many to choose from! Learning the basic principles of NAM, however, is easy. This page is the only part you need commit to memory! So let’s jump right in…


Just like many other elements of Sim City 4, the many options in the NAM are used by either “dragging” or “plopping”.

Simply put: drag a highway, plop a junction! Seem familiar?


There is one particular difference with the NAM from other mods and they are called Overrides. Many elements in the NAM are designed to be plopped and then dragged through. When this happens, they transform their initial appearance, updating and fitting itself into your design, overiding into a single, seamless network. Knowing what Overrides to use in the right place is where you’ll spend the most time learning in-game. This is the fun part as there are literally endless variations to choose from!


Within NAM’s menu you’ll find the following icons/categories. We’ll get into where and when to use each tool later on, so for now all we need to learn are the differences between them:

  • PUZZLE PIECES - A fixed, ploppable element that is static and does not override.
  • STARTER PIECES - A ploppable element that does override, telling the game to ignore it’s default tool and use your chosen starter piece instead. Example, plop a single 4-lane highway starter piece down and then drag through it with the highway tool to build a 4-lane highway! Easy.
  • FLEX PIECES - Another ploppable, pre-built element that does override. Example, you’ve built a highway but now you want to add a slip-road or ramp. Plop down a flex piece ramp directly on top and it’ll fit itself into your design just like that. Alternatively, drag though a piece and it’ll update. Flexible, wouldn’t you say?
  • HOLE/RAISER TOOL - A simple tool that allows you to dig a hole (for tunnels) or raise the terrain (for bridges).
  • ERASER - Unlike the standard in-game “Bulldozer” tool, the NAM’s Eraser allows minimal destruction! Erase one tile at a time.
  • TRANSIT-ENABLED LOTS - A piece that accepts more than one type of network. Example, a transit station, allowing sims to switch from riding a train to walking.


Simply choose your category from the menu, then use TAB to cycle forwards (SHIFT-TAB for backwards) through the loop of various options within that category. A hovering preview shows you what’s available. A small dialog box above that explains what that piece is. Don’t worry if some of the descriptions don’t make sense just yet — this guide will help there.

HOME and END keys allow you to rotate the piece on the map, just like buildings.

(Attention Steam Users: The Steam Overlay is set to use the key combination Shift-TAB by default. Through the Steam client, you will need to either change the key combination for the overlay, or disable it altogether in order to use cycle backwards through TAB loops)

Now let’s look at what everything is in the Overview