Im new to Revit; I imported a CAD survey file into my project, and yesterday had my 3D contoured site model up beautifully. Today, I can only see the model in section; no 3D or site plan. Please help!
Your post is a little cryptic. I think what you are saying is that yesterday and today are different. Is that about the size of it?
I think you need to check all worksets,
All the worksets should be visible.
either delete existing 3D view and create a new one or activate your bulb icon it could be hidden it that view and unhide. thanks
Post up the file so we can take a look. If you are using default Revit template, the Level 1 & 2 have Topographic set to off. Only site floor plan have them on. So check in Visibility/Graphics and turn on Topography. In 3d check and see if topographic is also turned off.
HI @Anonymous,
Welcome to the forum and thanks for posting.
As suggested by our community, we'll need more information from you. Some tips:

Wendy Lim
Architecture, Engineering & Construction Community Manager
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Let the acceleration work from Option bar and delete your CAD file from the model and see what happens may u move this CAD file and the site seems to be very wide.
Helloooo -- Jero Young. Are you still out there? A lot of people here betting you are. Got a story to tell us all?
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