From: Preservation and management of a World Heritage site Tajima Yahei Sericulture Farm and its buffer zone
Length of wall (in ken)
Length of opening (in ken)
Ratio of opening to wall (Opening ÷ Total length)
Front
13.5
9.0
0.67
Rear
6.0
0.44
East
5.0
3.0
0.60
West