It was on this day in 1968 that the US Secret Service took delivery of a new Presidential Limousine/parade car for Lyndon Johnson, widely rumoured to be the most expensive car ever built at that point in history.

Due to the astronomical research and development costs, unprecedented security features and meticulous construction, the Lincoln Convertible Executive, bankrolled by Ford, was conservatively estimated to cost $500,000 - a staggering amount at the time.

Measuring 21ft 6in in length and containing over two tons of armour plating, the limousine featured bullet-proof glass thicker than used in U.S Air Force fighters and ran on unique, heavy-duty truck tires which allowed for driving up to 50 miles at top speeds even if they were flat. Even today, many of the advanced technological features have never been revealed publicly.

Today the vehicle - which was also used for a few years by Richard Nixon - is one of the star attractions at the Lyndon Baines Johnson Museum situated in the ex-President's home town of Austin, Texas.

Sell or part ex your car today