The M25 ‘Magical Mystery’ tour

The grey stretch of tarmac that inspired Chris Rea's Road to Hell is about to become one of the country's most unusual tourist attractions. Surprisingly, there's no shortage of people keen to check out the delights of London's busiest motorway - when Brighton and Hove Bus and Coach company announced plans to launch a tour of the 119-mile circuit, it proved so popular that it sold out and additional dates were quickly added.

"The original idea came from my colleague Simon as a bit of a joke," admitted Ian Miller, coach operations manager.

"We honestly thought it would never run - why would anybody want to travel the whole circuit of the 'road to hell'? However, our drivers and guides worked hard to make the excursion incredibly interesting and very enjoyable - much to our initial surprise!"

So it was that I found myself in the glamorous surrounds of Hove coach station preparing to embark on a tour of the M25, that grey ribbon of tarmac encircling our capital. The tour started with a heavy dose of humour as we pulled out of the coach station, our guide welcomed us to the Mystery Tour of the M25, admitting that for many, the mystery might well be why such a tour exists.

Spectacular slip roads
Before joining the M25 and the other 196,000 vehicles which use it daily, we passed through Godstone and glimpsed the Highways Agency's hi-tech control centre responsible for the motorway's southern section.

As we joined the first stretch of the motorway, our guide was particularly excited to point out the Reigate Hill slip road - the country's longest at over a mile.

The next must-see was literally a high point - shortly after Reigate Hill came the highest point of the M25, where the road reached a dizzying height of 220 metres, with our guide wryly joking that it was "all downhill from here".

We sped on to Junction 13 - the only place where the M25 bridges the Thames - before passing Heathrow's T5 (apparently home to 16 miles of conveyor belts) and the Heathrow incinerator, which processes 500 tonnes of airport rubbish a day and helps to heat Heathrow's terminals.

We then passed under a motorway bridge built by Isambard Kingdom Brunel which is home to one of the country's most famous (and misinterpreted) pieces of graffiti, reading: "Give Peas a chance." Peas was actually the nickname of a graffiti artist who was eventually sent to prison. Peas had 'tagged' the wall with his name, and shortly after he was sent down, his friends added the additional words in a show of solidarity for their incarcerated friend.

Our guide announced the driver was due his rest break and we pulled into South Mimms services, the M25's only service station located on a bike route; in this case the National Cycle Network's route 12.

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Tunnel vision
As we travelled into Hertfordshire, Holmesdale tunnel loomed, followed by Bell Common tunnel in Essex, on top of which sits Epping Foresters cricket club. Developers built the tunnel by digging down into the hill through which the tunnel was to pass, before filling it in.

After the construction was completed, the cricket club reopened, making it the first cricket pitch atop a road tunnel. After passing retail behemoth Lakeside, our journey took us under the Queen Elizabeth II bridge, which was Europe's largest cable-supported bridge when the Queen opened it in 1991. It's also coach manager Ian's favourite part. "I love that bridge," he admits. "The amazing engineering and magnificent views from the top make it a true highlight."

The next highlight was a massive Sainsbury's depot, responsible for supplying all the stores in the south-east.

Apparently, locals concerned about construction of the building were placated with promises of a water feature, although their dreams of a fountain were shattered when the store's bosses revealed the water feature would actually be a sewage plant.

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Dark past
Bluewater shopping centre was next, before we passed Junction 3. The M25 has its dark side too; this is where Kenneth Noye, the man who helped distribute the proceeds of the 1983 Brinks-MAT robbery, stabbed Stephen Cameron to death in a road rage incident.

Legend has it that several members of London's gangland mafia have been interred in the supports of the motorway's 234 bridges, as well as being buried beneath it.

We carried on past Brands Hatch race track, before stopping for coffee at Clacket Lane service station. Its original name, Titsey Wood, was scrapped after the powers that be decided the name would turn the services into a laughing stock.

Back on the road, we completed the final stretch of motorway. As I made my way back to London on a packed and delayed commuter train, clutching the certificate which proved I'd survived the M25 Magical Mystery tour (yes, you get a certificate), I couldn't help but think that the M25 might just be a little bit magical, after all.

Tours of the M25 start on 22 March and cost £15. Visit the website for more information.