GraphicsPath.Widen Method (Pen)
Adds an additional outline to the path.
Assembly: System.Drawing (in System.Drawing.dll)
This method creates an outline around the original lines in this GraphicsPath, with a distance between the existing lines and the new outline equal to that of the width of the Pen used in the call to Widen. If you want to fill the space between the lines you must use the FillPath rather then the DrawPath.