IT’S gone — but the greatest mystery about the removal of the Coke sign in Kings Cross is what it revealed.

A series of colourful markings resembling a postmodern mural has baffled the City of Sydney, Coca-Cola and local heritage buffs.

“The City was unaware of the markings on the support wall and has been advised by Coca-Cola that they will be undisturbed during the restoration work,” City of Sydney spokeswoman said.

media_camera The markings had been covered by the world famous sign since 1974. Picture: John Appleyard

“The current building it is attached to was designed to support a large billboard.”

The sign’s famous red backing panels were stripped from their scaffolding this week, completing a total removal of the iconic sign to make way for a brighter replacement, due to arrive early next year.

Coke has promised not to damage the image, saying work was strictly confined to the billboard.

A white door can also be seen, which has allowed maintenance workers to access the sign for more than four decades.

“A temporary banner sign will be erected in the coming weeks while work continues,” a statement from Coca-Cola said.

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media_camera The hidden door has been one of the stranger discoveries behind the Coke sign. Picture: John Appleyard

Potts Point and Kings Cross Heritage Conservation Society president Andrew Woodhouse had no idea the image was there but believed it to be a 1970s mural.

Built in 1974, the sign became known as the “gateway to the Cross, featuring on music videos, TV, famous photographs and as a landmark meeting point.

Its 800 neon lights were switched off permanently in September for work to begin.

Anyone with information about the markings can contact nick.hansen@news.com.au.

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