AutoCAD 2008 User's
Guide > Share Data Between
Drawings and Applications > Work with Data in
Other Formats > Import, Attach, or
Open Other File Formats >
Attach DGN Files as Underlays
You can attach 2D geometry stored in a MicroStation DGN file as an underlay, a reference for additonal work.
MicroStation and AutoCAD are both CAD applications with some similarities, but they both use different terminology that is used by their user bases.
You can add or remove DGN underlays within drawing files, or you can change their position, scale, and orientation.
Once a DGN file is attached to your drawing as an underlay, this geometry remains visible and available as long as the DGN file can be located.
After attaching a DGN underlay, you can adjust the appearance of the underlay or set up clipping boundaries to focus on the specific part of the underlay.
You can view and manipulate DGN underlays and change paths to underlays from the External References palette.