How do I build real topography in Revit from Rhino contour lines?

Export only the contour curves from Rhino (Export Selected as DWG), then in Revit: Insert → Link CAD with Origin to Internal Origin at Level 0. Now Massing & Site → Toposolid → Create from Import, pick the linked DWG, and tick ONLY the layers holding the topo curves. The sketch boundary must be closed or it fails. Afterwards you can refine with Modify Sub-Elements and Split Lines. If you round-trip back to Rhino, export the Toposolid with Solids as ACIS (SAT) — mesh export gives you triangle soup. Full steps: Topography from contours →