Mesh to Curve from... Square?

Well, I can get a circle to go from a mesh to a curve, but I havent been able to get a square/rectilinear shaped object to become a curve from a mesh. Is this even possible?

Thanks!

Dawg

A closed square, not an open one.

it is possible.
#1 add a plane
#2 go to edit mode [TAB], select everything [A]
#3 delete [X] -> ‘only faces’
#4 go to object mode [TAB], convert to [ALT+C] -> ‘curve from mesh’