Creating a terrain from contours

I am looking for the best, or maybe quickest, way to produce 3D terrain from a 2D plan with contours, like this:

I can import all the lines satisfactorily into SU. I could easily create a kind of terraced appearance by making surfaces and raising each by a metre at a time, but that won’t represent a realistic impression of the gradations.

Suggestions can include native tools as well as extensions.

I think I have answered my own question by finding this tutorial: Terrain Modeling in SketchUp with Sandbox Tools - The SketchUp Essentials #31 - YouTube

Looks like Sandbox tools are made for the job.

With Fredo TopoShaper

ter-02

That’s interesting. The inbuilt sandbox tools work very well but if you start with contour lines in the same plane (as I did), you do have to spend time moving them. The extension seems to speed this up by allowing you to ascribe height data to the lines. Is that the main advantage?

I also think that TopoShaper creates a quadrilateral mesh instead of the heavily triangulated one by the Sandbox from Contours tool. Both have their uses.

Or you can use Elevate Contours plugin

Cheers. That certainly speeds things up.

What are the circumstances that would prefer one to the other? Does one make for a smaller file size, for example?

Autostarting at 0:33 (to 1:26)

Can Vertex Tools or Quadface Tools be used for any of this in place of Sandbox Bonus Tools?

@RTCool, try this to replace a surface of irregular triangles with a quadrilateral mesh