A 1960's Popemobile highlights Bonhams' Exceptional Motorcars and Motorcycles sale in California on August 19, 2011.
The 1964 Lincoln Continental Limousine, which has a high-end estimate of $350,000, was souped-up at the special request of the Vatican to convey the Pope through New York to address the United Nations on world peace.
The 21-foot vehicle was rushed to completion in less than two weeks during the autumn of 1965.
Exterior step plates and handrails for security, additional interior seating for aides and prelates, and a raised seat for the Pontiff were only a few of the many changes.
The most visible attribute of the collectible car is the transparent rear landaulet roof and roof-mounted windshield, which protected the Pope and his entourage while enabling the throngs of spectators that lined the parade route to see the Pontiff.
Following the Papal visit the Lincoln was loaned to the city of Chicago - after removal of the bubble top, Papal chair and associated internal fittings - where it served as a parade car and courtesy vehicle for visiting dignitaries.
In 1968 the Vatican once again called upon the machine for another Papal visit, this time to Bogotá, Colombia for the 39th Eucharistic Congress.
It subsequently transported returning astronauts on tickertape parades, first being employed for this use following the successful Apollo 8 mission in 1968.
The vehicle also received the first moonwalkers of the Apollo 11 mission as well as those from the near-disastrous Apollo 13 adventure. These famous names could well help boost its appeal with collectors.
Since being removed from service in the early 70s it has been carefully maintained in completely original and well preserved condition.
We will tell you how it gets on later in the month.
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