Revit Shared Coordinates and AutoCAD Civil 3D
Quick 5 minute video available on the right hand side of Revit Shared Coordinates & AutoCAD Civil 3D in action!
A Revit project has internal coordinates for all the elements that compose the model in a project. Those coordinates are known to this project only. This is acceptable if you have a standalone model whose position is not relevant to other models or to a site. However, if you want the position of the model to be known to other linked models, you need to share coordinates.
Tip: You should derive shared coordinates from only one file. That one file defines the coordinates for all other files that compose the project. Acquire coordinates from one file and then publish those coordinates to other files.