The school's Head of History, Susan Casey, says it is a remarkable find.
She is hoping money can be raised to conserve the shelter and turning it into a teaching facility.
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Victorian North Yorkshire railway station celebrates 150 years of operation
Newcastle International Airport has welcomed the recommendation by the Airports Commission that a third runway should be built at Heathrow.
Six former British soldiers, including three from this region, have been told today that they will go on trial in India on weapons charges.