What is thought to be the last surviving Morris London Taxi will demand a high fare from collectors this March 9, when it appears at the Historics at Brooklands auction.

What was meant to be ballast turned out to be an unwanted explosive addition

The 1929 cab, one of only 840 of its kind ever produced, will be sold with a £25,000-30,000 ($39,667-47,602) estimate. Its fascinating history brings a new element to an already exciting sale.

The car was first produced as an export model, designed to boost Morris' overseas sale. However, it saw poor demand abroad, causing the 1,700 made to be sent back to the UK, 840 of which were put to use as taxis in London.

Nicknamed Uncle Lima, the Morris saw a full decade of service, surviving the Blitz while ferrying London's businessmen across the capital, before being adapted by a farmer for use as a tractor as part of the war effort. During this time it was fitted with a piece of scrap metal for stability, which was later discovered to be two unexploded bombs and an anti-tank rocket.

Fortunately, the bombs have now been removed and the taxi has enjoyed a relatively peaceful life since. It was restored before taking part in the 1975 Commercial London to Brighton Run, and has been in constant use since.

The faithful Morris boasts a lively 15.9 hp engine with a four speed gearbox. This being Morris' 100th year, it is sure to attract attention from those celebrating the classic British manufacturer.

As every discerning classic car collector will know, the Scottsdale auctions in Arizona are getting underway this weekend, so be sure to visit our Classic Cars news section for all the results. For more, sign up to our free weekly newsletter.