Today in History - December 25: The grim reason hotel stairwell doors are always kept closed

A series of design flaws worsened a blaze that became the deadliest hotel blaze in history on December 25, 1971.

An explosion of propane gas being stored at a coffee shop on level two of the Daeyeonggak Hotel in Seoul, South Korea, created a massive inferno.

Because the stairwells lacked fireproof doors, what would have been the way out for hotel guests became a massive chimney, spreading smoke and fire throughout the building.

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In spite of being only two years old, the luxury hotel also lacked battery-operated exit lights.

As a result, guests and staff were unable to find their way out in the heavy smoke.

Firefighters arrived on scene but their ladders only reached as far as the eighth floor.

With no other way to evacuate people from the hotel, helicopters were dispatched.

Guests and staff were rescued from the roof using aerial slings.

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But many doors leading to the roof were locked, and masses of bodies were found by them.

Thirty-eight of the fatalities were people who fell to their deaths, including one who fell from the helicopter.

Others tried to jump to safety, many trying in vain to jump out of the window clutching the mattresses from their bed.

Sadly, rescuers also did not have air mattresses to break their fall.

A circus troupe was summoned with their trapeze nets, but to no avail.

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Archers fired arrows with ropes attached to try and reach the upper floors, but the ropes were too heavy.

In all, 164 people were killed and 63 were injured.

The death toll would have likely been higher if a number of companies with offices in the tower weren't closed for Christmas.

The building was remodelled and reopened three years later with stricter fire prevention methods.

When a fire broke out there in 2010, it was extinguished in 20 minutes with no injuries.

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