OFF-ROADING entered a new dimension when Mercedes took three of its new GLA compact SUVs 550ft underground.

Deep in the chambers of the Winsford Salt Mine in Cheshire we put the latest Mercedes through its paces on some of the 130 miles of road which exist below the surface.

It is the oldest operational mine in Britain and for more than 150 years has been producing millions of tons of salt now used to keep our roads ice free in the winter.

Down in the depths where temperatures are a constant 14C the new GLA traversed the 25ft high tunnels carved through the salt strata which extends from Northern Ireland across to mainland Europe.

With ultra bright headlamps supplemented by roof mounted spotlights the GLA looked the part for its subterranean expedition.

The GLA is Mercedes' entry into the compact crossover market and priced from £25,850 it has the likes of the Audi Q3 and even the top selling Range Rover Evoque in its sights.

From the underground exploits at Winsford it was out across the Peak District to sample the GLA's abilities in more conventional surroundings.

The car we tried was a top specification 220 CDI 4MATIC diesel in AMG Line trim which costs from £31,030.

It is available as a seven speed auto only and with the 2.1-litre engine developing 170bhp and plenty of mid-range torque it is a competent performer.

Top speed is 134mph and 0 to 60 takes 8.3 seconds yet it is nicely economical. Mercedes is claiming 55.4mpg with emissions of 132g/km and even on the ups and downs of the Peaks we managed to average 51 to the gallon according to the onboard computer.

Stop/start is standard on all models which also include a two-wheel-drive GLA 200 diesel and a GLA 250 two-litre petrol.

The GLA is based on the latest Mercedes A-Class hatch but is some two inches higher and four inches longer.

That translates into significantly more luggage space of 481 litres compared to 341 in the hatch and makes the GLA a little more family friendly although cabin space is about the same.

Its real attraction is a rugged persona with a raised ride height adding presence to its eye catching design. There is going to be plenty of kudos from being seen behind the wheel of a GLA, even if only on the school run.

Inside the GLA is a class act with the dashboard focused on a tablet-style display screen which sits proud of high quality trim and artificial leather upholstery.

With the gear selector mounted on the steering column and an electronic parking brake fitted to the right lower part of the dash, the centre console is clutter free with a good amount of onboard storage.

On the road the ride is nicely composed with no trade off as a result of the 4MATIC 4x4 configuration which works automatically diverting the drive from the front to rear axle as required.

The drive can be locked in if necessary for added traction and the car is also fitted with a hill descent system but realistically it is more of a soft-roader than full blown off-roader.

Safety systems are plentiful and include driver fatigue monitors and anti-collision radar which can be embellished with an optional driver assistance pack for £1,495 to include lane departure warnings and blind spot monitors as well as an automatic braking system which works at motorway speeds.

A reversing camera is standard fit and incorporates trajectory guides on the display screen to aid manoeuvring.

Although more expensive than the A-Class by some margin the GLA is going to hit the mark with a blend of practicality and prestige that is part of a new generation of SUVs from Mercedes.