If you are going to install a trampoline on your property, safety dictates that it be installed on level ground or on ground which has been raised or lowered in the right places to ensure a level trampoline surface. If not level the trampoline, normally a valuable fitness tool, could prove to be a dangerous one instead.
If the jumping surface of the trampoline is not level, the trampoline will tend to tip, rock, or slide when someone is jumping ...