Originally, the bunker was for everyone in the area to shelter from the threat of Japanese bombs during World War II, but the major concern was for the safety of school children.

The original school building in Church Street backed onto the main northern railway line which also runs through the town of Paterson.

It was a real and terrifying threat in war time that the railway line and bridge in the centre of town would be targeted.

The children would march across the road to practice getting inside the shelter for 20 minutes, once a week.

It was built on Mr Ingram's property opposite the school so they would not have far to go.

They would take a sandwich and drink into the shelter which had enough space for 25 to 40 students.

Fortunately, an air raid never happened.

Today, the air raid shelter, unique in the Hunter Valley, remains in the backyard of Judy and Doug Styman and is an attraction on the Paterson Historic Town Walk.

"It was dug into the side of a hill, quarry stone was placed at the entrance, there is a trench at the back and a breather hole," Mrs Styman said.

"The bunker is made with railway sleepers, it is paper lined and topped with dirt."

Explosives from Martins Creek quarry were used to loosen the ground.

Not only is it an attraction to 21st century school students and curious visitors, the cool, dark bunker is now home to a possum and micro bats.

The shelter entrance resembles the opening to a cave or a mine.

"For us, it is something that is on our property, but we are happy for people to see it," Mrs Styman said.

"It has always been here and it was a place for our children to play in and have fun."

The bunker can be seen during Paterson Historic Town Walk on March 15.