Image copyright AP Image caption Scottish councils made preparations for the threat of a nuclear attack

The crisis in Ukraine has led to talk of a new cold war between Russia and the West. But, of course, the real Cold War was different.

For more than 40 years from the end of World War Two, the world stood on the precipice of a catastrophe. A fear that East-West tensions could spill over into nuclear war.

In Scotland, as elsewhere, civil authorities had to prepare plans for the unthinkable.

Files, once secret, are kept in the archives of Glasgow's Mitchell Library.

They give some idea of how Scottish councils would have responded to the threat of a nuclear attack and what they feared would happen.

Image copyright Thinkstock Image caption The council plans detail the likely damage to Glasgow in the event of a nuclear strike

The documents run from the late 1940s until the mid 1960s.

Risk of radiation

One of the most chilling files is a secret report from the Home Office produced in January 1953.

The report assesses the likely damage and casualty numbers from an atomic attack on Glasgow. It looks at the specific factors affecting the city such as how the population is spread at different times of the day and how a large proportion of the population live in tenements.

It presumes that an atomic bomb exploded at 2,000ft above Glasgow Bridge to maximise the damage. It assumes only superficial damage outside a distance of 2-2.5 miles from the explosion.

Image copyright Reuters Image caption The report says tenements could lead to "graver rescue problems" if they collapsed

The report says tenements would not offer appreciably greater protection from blast than small brick-built houses - but could lead to "graver rescue problems" if they collapsed.

It also suggests the weight of their construction could provide more protection from the risk of radiation for survivors.

The report calculates possible casualty figures too. It says 60,000 killed and 20,000 seriously injured in a night-time attack but 80,000 could die if the attack came by day.

Another specific risk was from fire. Tenements were seen as a high fire risk: the brilliant light of the flash of the explosion could enter several windows while there was also a greater chance of secondary fires.

One fear was of a ring of fire and a risk of a conflagration which could result in 16,000 more deaths.

Another report from 1953 looks at the much greater risk from a hydrogen bomb - total destruction for four miles and severe damage for 10.

Evacuation schemes

Military strategists always thought it unlikely an atomic attack would come without warning, out of the blue. It would probably have followed a period of heightened international tension and a period of conventional warfare.

With this in mind, schemes were discussed for the evacuation of the parts of Scotland most at risk.

A meeting took place in St Andrews House in Edinburgh involving councils and the Scottish Office's Department of Health in December 1956.

Image copyright Thinkstock Image caption Glasgow Central Station was a key location in the council's evacuation plans

It discussed the possibility of a plan for the evacuation of children, expectant mothers and the aged and infirm which could be put into place at short notice.

Up to 1.1 million people could have left their homes - mostly from Glasgow, the area immediately surrounding it, Edinburgh and Rosyth.

They would have been billeted with householders in areas such as Ayrshire, Argyllshire and the Highlands.

The plans were discussed again over the next few years. One of the last documents in the collection is from 1965. It looks at the times special trains might run from Glasgow's two main railway stations.

Tourist attractions

Schemes were also prepared by Glasgow's department of education in 1951 and 1956 for a possible evacuation scheme involving children.

In a sign of other aspects of the time, it distinguishes between Catholic and Protestant children and attempts to ensure Catholic children are sent to areas where the church has facilities.

At times during the Cold War, the threat of a real war appeared imminent: especially during the Cuban Missile Crisis in October 1962.

A draft memorandum from the Scottish Department of Health from 24 October 1962 outlines details of an evacuation scheme. It makes no reference to the crisis but it seems unlikely the timing is a complete coincidence. If nothing else, it is bound to have been in the minds of officials.

That week is now generally accepted as the date when the world came closest to a nuclear war.

The Cold War thawed with the collapse of the Soviet Union in the early 1990s.

Much of the Cold War civil defence system has now been dismantled while some bunkers are even tourist attractions. Documents like those held by Glasgow paint a fascinating but also terrifying picture of what might have been.