HOW do you replace an icon? Porsche and Volkswagen managed it with the 911 and the Golf respectively, but Renault couldn’t come up with a like-for-like replacement for the Supercinq and Peugeot has spent 30 years trying to build a ‘new’ 205 GTi.

Land Rover has procrastinated over the Defender even longer than that.

It first had a stab at a replacement in the early 1970s with the SD5, a ‘modernised’ version of the chunky Defender which looked , from some angles, like the bastard off-spring of an unlikely liaison between a Toyota Hilux pick-up and a Talbot Rancho. Thank God that one didn’t get off the ground.

Somehow, Land Rover has managed to keep the Defender alive – albeit less and less relevant to the SUV mainstream - into the second decade of the 21st Century. That’s 68 years since Maurice Wilkes dreamt up a plan to build a rugged utility vehicle to give the Willys Jeep a run for its money.

In that time the Land Rover – dubbed the Defender since 1983 – has become Britain’s best-known car.

The shape is unique - and so is the driving experience which, if I’m being brutal, is pretty dreadful if you’re not off road. That said, for a small but incredibly loyal group of Defender fans nothing else will do.

But nothing lasts forever and 2015 will be the Defender’s last year in UK production. It’s had a good run by the old warhorse has reached the end of the road.

To make sure the Defender goes out with a bang, rather than a whimper, Land Rover bosses are planning a year-long celebration of their first vehicle.

And, in the best time-honoured traditions of the British motor industry, what better way to start that with a new special edition? Actually, three new special editions.

The exclusive Autobiography Edition promises more performance, luxury and comfort than ever before thanks to its comprehensive equipment list, unique duo-tone paintwork, full Windsor leather upholstery and a power upgrade from 122PS to 150PS. Exclusivity comes as standard as only 80 Defender Autobiography Editions will be available in the UK.

It will be produced exclusively as a 90 Station Wagon and priced from £61,845.

The Heritage Edition is inspired by early Land Rover models and mixes nostalgic design cues with modern creature comforts. It will be identified by distinctive Grasmere Green paintwork and a contrasting white roof. A heritage grille and HUE 166 graphics, recalling the registration plate of the first ever pre-production Land Rover nicknamed ‘Huey’, also identify the Heritage model.

This one hits showrooms from August with production limited to 400 in the UK. Prices will start from £27,800.

The exciting new Adventure Edition is aimed at Land Rover customers who relish the great outdoors and embrace the Defender’s ‘go anywhere, do anything’ attitude. It comes fitted with additional underbody protection and Goodyear MT/R tyres to boost the Defender’s already class-leading all-terrain capability. Unique decals and a leather-trimmed cabin ensure the Adventure Edition stands out from the Defender crowd.

A total of 600 Adventure Editions are available in the UK priced at £43,495 for all versions.

In the meantime work is progressing on a modern re-interpretation of the Defender that will carry the badge from next year.

It won’t be the veteran Defender, but Land Rover promises it will have the heart – and unique looks - of the old stager with the driving manners and refinement of a more modern design.

And that will be it for the original Defender – or possibly not.

Buried in the press release announcing the new specials was this tantalising titbit: “Land Rover is also investigating the possibility of maintaining production of the current Defender at an overseas production facility, after the close of UK manufacturing. Any continuation would see low volume production maintained for sale outside the EU.”

Perhaps the old warhorse might live to fight another day after all.