Extract/create a spline along a ridge of a mesh?

I’m very new to Rhino and Grasshopper and have tried some searches for this but I may be using the incorrect operative words.

I’m trying to make a multiple point line that follows an edge of a ridge. Can I do this with some sort of slope input?

What’s the geometry of the mesh edge like? Do you want a line that hits each vertex on the mesh edge or is interpolated/averaged through it? Please upload the 3dm and any GH file with the mesh and anything else that can help explain what you’re after.