The spline is a model of a plastic fencing of the type used in the ski fields. It can be placed to prevent skiers getting too close to the chairlift mechanism and chairs.
The fence is designed to be a maximum of 1.2 metres above ground level but can be raised or lowered to any level to suit. This allows a lower fence to be used, by embedding it further into the ground. It may be bent to a suitable shape.
Generally make the ground the correct shape and then place the fence, which will conform to the ground. If you place the fence and then raise or lower the ground, you will need to raise or lower the fence separately.
Use the shift key when placing or moving fences if you do not want them to connect to a previously placed fence.
Once installed you will find the fence as Ski Fencing in the Australia building splines listing.