Blueprints for the original World Trade Center have gone on sale at the New York International Antiquarian Book Fair on Friday after a Colorado man pulled them out of the trash.

The set of plans for sale represents the largest floor plan of the Twin Towers complex ever offered for sale, according to the New York-based Janes Cummins Bookseller. Cummins told the Associated Press that he expected the sale to be in the six figures.

The plans date from the 1960s. At the time of its opening in 1973, the World Trade Center in Manhattan was the world's tallest building.

Read more: Opinion: September 11 was a historic turning point

Plan of the World Trade Center complex

Almost lost to history

The blueprints left New York in the 1970s when architect Joseph Solomon took them to Denver, Colorado, with him when he moved away from New York.

His daughter threw them out in 2018, not realizing their value. A Denver resident found them in the trash and recognized them, noticing the references to Tower A and Tower B.

The New York World Trade Center complex, referred to as the Twin Towers, was an iconic part of the city skyline until it was destroyed on September 11, 2001, in a terrorist attack by al Qaeda.

The 9/11 Memorial and Museum said it does not have a full set of blueprints, and the Port Authority of New York and New Jersey said

it's unsure if it has one.

The Antiquarian Book Fair runs until Sunday in New York.

Front page of the World Trade Center blueprints

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