Definition: The word 'going' in British horse terminology is equivalent to the North American term 'footing'. Footing and going refer to the condition of the surface you are riding on. If the footing is heavy, it will mean you are riding through mud or deep sand. Hard footing or going would be hard packed clay or dried ground. Slippery going would be slick mud, or frozen ground. Good footing or going is a surface that the horse finds easy, safe and comfortable to travel over.

Examples:

After the rain, the going in the jumper course became very heavy.