And I thought IT projects took a long time

While IT projects frequently takes years to complete, it turns out that that's nothing compared to other tasks in the past.

Prehistoric cave paintings took up to 20,000 years to complete

It may have taken Michelangelo four long years to paint his fresco on the ceiling of the Sistine Chapel, but his earliest predecessors spent considerably longer perfecting their own masterpieces.

By comparing the ratio of uranium to thorium in the thin layers on top of the cave art, researchers were able to calculate the age of the paintings

Scientists have discovered that prehistoric cave paintings took up to 20,000 years to complete.

Rather than being created in one session, as archaeologists previously thought, many of the works discovered across Europe were produced over hundreds of generations who added to, refreshed and painted over the original pieces of art.

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The scientists have used their technique to date a series of famous Palaeolithic paintings in Altamira cave near Santillana del Mar, northern Spain. Known as the "Sistine Chapel of the Palaeolithic", the elaborate works were thought to date from around 14,000 years ago.

But in research published today by the Natural Environment Research Council's new website Planet Earth, Dr Pike discovered some of the paintings were between 25,000 and 35,000 years old. The youngest paintings in the cave were 11,000 years old.

Dr Pike said: "We have found that most of these caves were not painting in one go, but the painting spanned up to 20,000 years. This goes against what the archaeologists who excavated in the caves and found archaeology for just one period.

That just blows my mind. Think of the staggering amount of time involved.

The original research is published here