Need to draw some extra paths or make divisions within the park surface? This video shows you a few method for drawing and projecting/splitting surfaces.
Tools used:
DupBorder
Offset (O)
Extrude (EXT)
Extend (EX)
SetPT (only z axis selected)
Project
Project Crvs to Srf
Split (SP)
Join (J)
MergeAllCoplanarFaces