Never ride a tandem alone. The higher the density of population and amount of passing traffic, the more you will be heckled. Everyone who yells "Oi - your mate's fallen off" believes it to be the first time anyone has coined this particular helpful hint. Reckon on hearing it about once every mile, until you find a companion to double the power, halve the heckling and maximise the pleasure of pedalling around Britain. If riding a bike is good, sharing a tandem is more than twice as good.

The rationale

Cycling is certainly not as consistently wonderful as it is sometimes supposed to be. For every long, downhill cruise through superb countryside, there is a wet and windy slog up a hill whose chief attributes, besides a gradient of absurd proportions, are excess traffic and dismal landscapes of hypermarkets and obsolete factories. But there is no better way to see Britain than from a pair of handlebars supporting you at a stately angle, while you enjoy the 180-degree vision of the nation; next time you are in car, look at how restricted the view really is.

The good thing about a car (apart from keeping you dry, climbing hills effortlessly, etc) is that you can share your view of the truck in front with a friend. Mostly, bikes preclude conversation except among the most loud-mouthed or reckless of cyclists. A bicycle made for two addresses this problem, enabling the sort of inconsequential exchanges that make walking such a joy. More practically, it also helps with the hills - the power-to-weight ratio of two people is higher than one.

The realisation

Before you can experience these benefits (and the inevitable heckling), you have to find your tandem. You need not enquire of too many cycle dealers to realise they are all pointing in the same direction: towards a small town in the extreme east of Kent, and towards Arthur Lock in particular. "No, we don't do tandems here - you want to see Arthur down in Sandwich" is the inevitable response.

Arthur Lock of Sandwich is the high priest of tandemry. He runs a family business that is twice as old as his 62 years. His premises comprise a sprawling old laundry filling the middle of Sandwich. Mr Lock sells, on average, one tandem a week to devotees brave enough to disentangle their choice from the muddle of machinery around them. About a decade's worth of tandems seem to be breeding, given the number of child's trikes which surround them in a surreal "Tandems'R'Us" family portrait.

"We don't want an image like Halford's - a proper bike shop has to look like a junk yard" says Mr Lock, surveying the quasi-organic heap that supports his assertion. He builds tandems himself, using wheel rims imported from India ("The only place where they know how to make them strong enough"), but they cost over pounds 1,000 each. I wanted to be be-tandemmed in time for National Bike Week (beginning today), but I wasn't even sure how much I would enjoy company. So I peered into the rusting gloom for something a little more, er, secondhand.

She shone back, the colour of ripe cheddar or bright piccalilli, her stout mudguards as yellow as her heavy-duty frame. She looked capable of 0-12mph in a couple of minutes, and old enough (about 20 years) to be open to a little negotiation on her pounds 259 price tag.

Ten minutes and pounds 220 later, we were united by a lurid purple padlock that Arthur Lock threw in either as a kind gesture or a poor pun. I continued the bad joke in a little private naming ceremony; given the town in which I bought her, and her dazzling colour, she had to be Cheese & Pickle.

The ride

She may lack the pulling power of a turbo-charged sports car, but anyone in possession of a bright yellow tandem need not wait long - nor sit up and beg - for a companion to take a seat.

From Sandwich, we set off towards the sea, with the tandem performing all kinds of tricks unavailable to those in sports cars, such as dodging the pounds 3 toll for crossing the Sandwich Estate, and slipping through a narrow gate to the shore.

We scrunched along a shingle path above the beach. Where the land and the sea abandoned the horizon, the sky took over. On a laudably large stage, a repertoire of balletic cloud formations that would have been wasted on those in mere motor cars scudded by.

Deal slunk up out of the shingle, its double-yellow lines deterring motorists but merely mirroring the bicycle. Cars do not lend themselves to impromptu sightseeing. Drivers have to find somewhere safe to stop and park without penalty, a performance that is bound to deter casual halts. To the cyclist, though, a sudden heap of stones like Deal Castle is an invitation to further investigation.

The countryside is where the tandem begins to accrue greenie points at a tremendous pace. Noiselessly we proceeded past fields of rape (neatly camouflaging the bike) and lambs grazing greedily on tufts of turf. Seawash gave way to birdsong and added another layer to the multi-media experience. And, miraculously, the distance of two feet between sets of ears meant that the gratifyingly inconsequential conversations that are usual among hikers were able to proceed naturally.

Occasionally a car would come along and disrupt the cosiness, but it was heartening to see how much extra respect a tandem commands - the only exception being an unnecessarily intrusive French coach, appearing as we began the long sweep around the White Cliffs into Dover. The momentum seemed sufficient to sweep us along the prom and into the railway station. Here's something else you can't do with a sports car: put it on a train and rest your legs, while feeling morally uplifted after a day out without poisoning the planet. Cheese & Pickle's colour scheme clashed mightily with the train's livery, but the guard didn't mind a bit. Cheese & Pickle now sits in my living room, impeding (and impressing) guests and clashing with everything. But despite her inconveniently long wheelbase, my bicycle made for two adds an extra dimension to travel - and is forgiven everything.