Because of its length, the engineering crew decided to start the work from six places. As well as at the two ends of the tunnel, excavations were begun at two points on the mountainside, and at two points from the sea.
由於這條隧道實在太長了，為了趕工，工程人員分六個工作面同時開挖，除了由南北兩端對挖之外，還從山凹打了兩個斜坑，從海邊開了兩條便道一起開挖。