2.3.4 - Approach Roads
Step Description:
1. On the Create Roundabout - Approach Roads dialog box, set the desired options for the following settings:
- Predefined parameters to import
- Approach road parameters
- Style
- Layer
- Name prefix
- Labels

2. Click the Next > button to proceed to the next roundabout dialog box.
AutoCAD Civil 3D 2012 User's Guide reference:
User's Guide - Dialog Box Reference - Intersections and Roundabouts Dialog Boxes - Create Roundabout - Approach Roads Dialog Box
For more information watch the video below:
Create Roundabout (WMV)