it is within a distance of 1 kilometre from the perimeter of a scheduled monument and is 15 metres or more in height, or has an area of 0.2 hectares or more;
bod o fewn pellter o 1 cilometr o berimedr heneb gofrestredig ac yn 15 metr o uchder neu’n uwch, neu gydag arwynebedd o 0.2 hectar neu fwy;