I will make the lanes 1.2m (4 feet) wide then to save some dirt for the jumps. I already have a 30cm (1 foot) high wooden ramp that I made, and it has already been treated against rotting, so I think I will use it.

PS, I will not have to do any digging because I am buying the dirt from a garden centre, as I am not allowed to dig in the back yard (we only rent our house).

Sorry to sound like a complete treehugger in my last post. The truth is, even though I am only 12, I care a lot about the environment. I think it is so idiotic of some people to hunt whales, club seals etc., mostly for fun.

I want to make my track as eco-friendly as possible, such as using dead logs (we have a forest next to our house) for the sides of the track and a mixture of compost for the dirt etc.