The Network Addon Mod, or NAM, is a modification for SimCity 4 Deluxe (or SimCity 4 with the Rush Hour Expansion pack), which adds a myriad of new transport network items, ranging from ground light rail, to fractional-angle roads, to roundabouts, and much more. It also includes bugfixes to Maxis items and a highly optimized set of traffic simulator plugins, improving pathfinding accuracy and performance.

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This new release brings with it a number of exciting new features, and for the first time in NAM history, is offered in a single cross-platform package, which will work on Windows, macOS, and Linux right out of the box (provided one already has the required Java Runtime Environment installed). For more details on requirements and installation procedure, check the official download page.

SA 18 Jun  1 6531549706550

Features List

  • The NAM has switched over to a new Java-based installer designed by daeley, with cross-platform support for any operating system that supports
    the Java Runtime Environment (JRE).
  • The RealHighway (RHW) system has undergone a massive code overhaul ("Mark IV"), greatly improving stability, especially in compact situations. Diagonal x Diagonal (DxD) crossings (grade-separated) between wider RHW networks should now be possible in most situations.
  • The RealRailway (RRW) system is now the default (and only) option for the Rail network. Users wishing to retain the original Maxis Railshould download the separate Maxis Rail Legacy Plugin, when it becomes available.
  • Various cosmetic/legacy plugins, such as the Bullet Train Mod (BTM) and El-Rail Alternate Implementation, are no longer directly available within the main NAM download, due to crosslink and support issues. They will be available as separate downloads, as Legacy Plugins with no guarantee of support or further upgrades.
  • An initial basic version of the RealExpressway (REW) mod is now available.
  • A pathing issue affecting intersections with the Diagonal Streets Plugin, dating back to NAM 20 (!) has now been fixed (thanks to McDuell).
  • RRW Fractional Angle and FlexTrack switch content can now be constructed using easier-to-use FLEX Pieces, rather than memorizing drag/draw patterns. Some limited Fractional Angle elevated support is now available.
  • The Road-based Single-Tile and Dual-Tile Network Widening Mod (NWM) networks now support Multi-Radius Curves (MRCs). For the single-tile networks, override the base Road MRCs with the appropriate NWM network to convert them, and use the dedicated pieces for the dual-tile versions (the RD-6 uses an override of the TLA-5 version--place Road stubs to fill in the "bites" on the RD-6 R4 curve).
  • L3 and L4 FLEXFly pieces are now available for the RHW.
  • RHW FlexSPUI has been redesigned, with improved support for the current array of RHW networks. Support for L0 and L2 is present (use the legacy TuLEP OnSlope to connect to the L2 version).
  • Orthogonal TLA-3 and AVE-2 connections to the One-Way Road Roundabouts are now supported.
  • Three new RHW FLEXRamps are now supported: Type D1-Inside (RHW-4 base), Type E1-Inside (RHW-4 base), and Type D1-Inside Dual Shift (RHW-6C base).
    Additionally, L1 and L2 support has been added to the Type A2 ramps for the RHW-8C and RHW-10S networks, and the L1 and L2 versions of the RHW-3 network now support Type A1 and B1 ramps.
  • Various "tidal flow"-related pathing issues with the Draggable Elevated One-Way Road Viaducts have been addressed.
  • File encoding issues with certain NAM files that have been known to cause crash-to-desktop (CTD) errors with Aspyr's new 64-bit macOS port of SimCity 4 (currently just the App Store version) have been fixed.
  • A new bridge has been added for the NWM's NRD-4 network.

Changes since the NAM 37 Release Candidate of 23/24 April 2020

  • The new FlexSPUI V2 now works properly in LHD mode.
  • Drag pattern interference between the new draggable Road Small 90° Curve and the Road Long FA3 (71.6°) curve has been eliminated.
  • Issues with various RHW and NWM bridges have been addressed, including the RHW-4 Small Steel Arch, the RHW-6S Concrete Arch Dual, and the NRD-4 Thru Truss. The accidentally-omitted
    DDRHW-4 bridge has also (again) be re-added.
  • Missing textures/paths on some RHW T-intersections involving diagonals have been addressed.
  • New draggable Road curves (Small 90° and Small S) have received Euro texture support.
  • Issues involving the L1 RHW-8C crossings over Avenue have been addressed.
  • Pathing for the RHW-3-to-ARD-3 transition has been fixed.
  • The texture for the OWR-3 x OWR-2 +-intersection has been rotated to the correct direction.
  • Tidal flow issues with the Slip Lane functionality, causing paths to not function in certain directions (esp. in LHD) have been fixed.
  • Various Euro texture issues with the RHW-8C Type D1 ramp have been fixed.
  • The OWR-1-to-MIS transition has been fixed.
  • Avenue-to-MIS transitions have been fixed.
  • Both US and EU textures for the RHW-6C and 8C Type D1 Dual Shift Inside FLEXRamp have been fixed.
  • Various fixes have been made to the RealRailway (RRW) network.
  • Pathing fixes have been made to the draggable Wide-Radius Curve (WRC)/Multi-Radius Curve (MRC) and Fractional Angle (FA) functionality.
  • TLA Center Turn Arrow cosmetic mod now installed as option under Texture and Drive Side options, fixing previous file architecture issues.
  • Mac-only issues with GHSR network showing Monorail supports have been fixed.
  • Some INRUL-based issues with the RRW FlexTrack system have been addressed, particularly with the J2 Turnout (Ortho-to-FARR-1.33/1.5). Note that these changes have altered the availability of some drag patterns, and clicking on some existing switches may break them. Such switches will need to be rebuilt using their FLEX Piece equivalent.
  • Note that no new features have been added since the NAM 37 Release Candidate. Addition of new content will resume with NAM 38 development.

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This release is dedicated to David Edgren (dedgren) and his family--we wish you the best.

And thank you to all the members of the SC4 community for their patience, through this record-long development cycle, and for the continued support of the NAM Team, now in its 16th year of operation!

-The NAM Team

SimCity 4 NAM Development Entry 18-1: RealHighways Get An "Easy Button" (Literally)

SimCity 4 NAM Development Entry 18-1: RealHighways Get An "Easy Button" (Literally)

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Sneak peek at the next evolution in SC4 turn lanes.

Network Addon Mod 35 Released for SimCity 4

Network Addon Mod 35 Released for SimCity 4

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The NAM Team is pleased to announce the official release of the 35th edition of the Network Addon Mod, NAM 35, for EA Maxis' 2003 title SimCity 4. NAM...

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Network Addon Mod - Version 38 [Cross-Platform]

Network Addon Mod - Version 38 [Cross-Platform]

Full Version

The Network Addon Mod (NAM) combines all transportation network-related fixes, additions and new creations that have been released so far. It will add...

The Bay

The Bay

Prefabs 2 comments

A secluded inlet fed by a river descending from the surrounding cradle of mountains provides the perfect spot to build a town or two, or even a thriving...

Comments  (0 - 10 of 172)

What new methods of transportation did you add? (And also ambient vehicles, like maybe hot air balloons?)

Also, how can I add it to my game? Under which files do I put it? (I'm running SimCity rush hour on windows 7)

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TarkusSC4 Creator

The list of additions to the game's transportation networks is probably too long to list. Note, however, we did not add any new transit types per se, and ambient vehicles are more something we leave up to third parties.

The mod has an installer, which, since it's Java-based, is a .jar file and not a .exe file, and will need the Java Runtime Environment (JRE) in order to run. Also make sure you patch the game to be Large Address Aware (LAA) using the enclosed 4gb_patch.exe file, as this is a big mod that requires more access to RAM (and without the patch, the game will crash). Simply putting the files in Plugins without running the installer will have no effect.

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It crashes on the loading menu when I load a map. Only deleting the mod fixes it. I've even installed the 4gb patch and tried the launcher and everything. Nothing's working

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TarkusSC4 Creator

Which version of SC4 are you running? The 4GB Patch will prevent NAM 37-specific crashes, even if you have less than 4GB RAM, so something most likely went wrong with your patching.

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I'm attempting to use the mod, but when I go to load a city from the main map, the game crashes to windows. If I go in and disable/don't install aspects of the mod, I can get the game to run and can see at least some of the mods, but none of them appear to work.
I've tried looking up a resolution for this, but my search has come up empty... maybe I'm looking in all the wrong places.
Is someone able to help me troubleshoot this please?
Older computer. 8G ram, 64bit, Intel iS-2500 chip.

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TarkusSC4 Creator

Check the 0-read-first-nam37.html file included in the download itself. It has all the info you need, but I'll supply it here as well.

NAM 37 requires that the game be patched with a "4GB patch" to be Large Address Aware (LAA), meaning that it can access 4GB RAM instead of a mere 2GB. Without being patched, the game will crash upon loading.

The installation package includes the NTCore 4GB Patch--the patch file is named 4gb_patch.exe. Open this file, point it to the SimCity 4.exe file in the game's installation directory, and click "Open". You should then get a window with an "Executable successfully patched!" message. Click the "OK" button. Your game is now successfully patched to be Large Address Aware, and you can run NAM 37 without issue.

For reference, these are the default locations of the SimCity 4.exe file in the available and compatible versions of the game:

GOG: C:\GOG Games\SimCity 4 Deluxe Edition\Apps

Steam: C:\Program Files (x86)\Steam\steamapps\Common\SimCity 4 Deluxe\Apps

Disc: C:\Program Files (x86)\Maxis\SimCity 4 Deluxe\Apps

(Origin: C:\Program Files (x86)\Origin Games\SimCity 4 Deluxe Edition\Apps--note that copies purchased from the Origin Store are not supported, due to being unpatched and unpatchable. Ask for a refund. If your copy was obtained by redeeming a CD Key with Origin support, it is patched. Check the version number on the executable if you remain unsure. 1.1.641 = fully patched, 1.1.610 = unpatched, unpatchable, and incompatible.)

While all NAM versions over the past 6+ years have incorporated a routine to apply the 4GB patch, do not assume you automatically have already applied it and are ready to use NAM 37 out of the gate. If you've changed from disc to digital in the time since NAM 36 was released, or have swapped to a different digital edition, the edition you are now using will need patching.

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Worked like a charm. Thank you for the quick reply!

I had forgotten to mention I was working off the Steam load.

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If I download it from steam, then in which files do I place it? Plugins folder?

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TarkusSC4 Creator

The mod comes with an installer, which will take care of that for you. Extracting the contents of the download into Plugins won't do anything, and manual installs aren't really possible (or advisable), due to the complexity of it.

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