A WARTIME air raid shelter containing an 80-year-old bottle of Pepsi was unearthed by unsuspecting builders at an army base.

Workers uncovered the Second World War shelter at Dalton Barracks near Abingdon, while installing a new multi-million pound heating system.

The structure, inside which families once fled as the bomb siren sounded, had been submerged in soil for decades and still housed items from the era.

Contractors for CarillionAmey, responsible for maintenance and repairs at Armed Forces accommodation sites, discovered the structure during a £3.3m project to replace the heating system at the barracks in Shippon.

A spokesperson for the company said: “Construction work never fails to throw up a surprise and, despite analysis of drawings and surveys before starting the job, we never anticipated to find such a structure that clearly has some history.

“When we were finally able to fully excavate we found a glass Pepsi cola bottle dated 1936.

“Although not expected, it is not unusual to find buried objects, given the age and historic nature of these sites.”

The discovery was made in February but only announced publicly last week, but has not delayed the project.

Builders were able to continue work once the shelter was inspected and found to be safe.

Workers drained the shelter of standing water and a team from one of the on-site regiments ensured any unidentified objects were not harmful.

The spokesperson added: “It was a surprise to find the air raid shelter but something we do come across.

“We had the experience to deal with the situation effectively.

“This has been an interesting find but has not impacted upon the delivery of this important work for the site.”

The shelter will soon be fully excavated and cleared internally, and filled in order for work above ground to continue.

Builders had been in the middle of lowering plant rooms onto the site to house parts of the heating system.

The current heating system was described by CarillionAmey as ‘old and tired’ and prone to breakdowns.

Its replacement will supply a dedicated heating and hot water resource to 14 barracks blocks, serving up to 650 people.

CarillionAmey operates independently from its parent company Carillion, and said it was not affected by the latter’s collapse earlier this year.

It holds contracts with the Ministry of Defence to look after service accommodation, including Dalton Barracks.

The site is home to 3 Regiment Royal Logistic Corps, 4 Regiment Royal Logistic Corps, 21 Military Intelligence Company and 2 Military Intelligence Battalion.

Completion of the heating system is expected in June this year.