He made this go straight up for a short distance, then curved it to the level, above the original tunnel.

It is currently split in three parts - the firing range, a section of original tunnel, and the shelter.

During the tourist season, the first 85 feet of the original tunnel is opened daily for visitors.

The original tunnel was filled in with concrete to prevent it being used again.

The only way in, then, was through the original tunnel.

Now they had to figure a way around it, intersecting their original tunnel on the other side.

The original 1960s-built tunnel was slated as of one the least safe in Europe in 2000, according to a study.

Although the original tunnel is closed there is also a bush walk that will take you close to its entrance.

Eventually, a compromise was worked out, and the third tube opened on May 25, 1957 to the south of the original two tunnels.

The original tunnel might even have been a decoy.