The surrounding mound still rises to a height of 2 metres ( 6.6 ft ) in places .
Calculations suggest an original volume of at least 200 cubic metres ( 7,100 cu ft ) .
The surrounding mound still rises to a height of 2 metres ( 6.6 ft ) in places , and calculations suggest an original volume of at least 200 cubic metres ( 7,100 cu ft ) .