Love in a city where there's barely room to stand; tradition nestling up against modernity. Jeremy Atiyah tackles the big themes Japanese-style
You don't have to be an adulterer but it probably helps. The love hotel I visited had dimly lit torsos of naked Greek gods in the foyer. A digitally recorded voice whispered irrishaimase ("welcome!") and doors closed secretively behind my back.

Sleaze? No, just anonymity, Japanese-style, though as it happened a couple of flushed high-school kids were shuffling out as I entered. Nobody cared. The receptionist was behind an opaque wall of frosted glass but we couldn't resist bending to peer politely at each other through the ticket window. I booked a room at pounds 25 for the hour. Here in the Shibuya district, upmarket love hotels have rooms with names like the Graceland Suite. Mine just offered the basics: a nicely packaged condom on the pillow, a dispensing machine with dildos, potency tablets and anal vibrators. I availed myself of the coffee making facilities, reclined on the futon and turned on the TV. All in all, a highly convenient way to kill a couple of hours on a rainy Tokyo afternoon.

The Japanese capital was not just a city of vast corporations, expressways and smog, then. I was doing a round of Tokyo's hotels, in search of its various faces and love had seemed the finest place to start.

Out in Shibuya after dark, towering blocks were ablaze with neon. Problems such as ageing did not occur here. Ranks of divinely young people, 20 or 30 deep, floated leisurely across the roads. Dudes with long hair and suntans stood on corners; crowds of decadent girls flowed from department stores.

Tokyo high-school girls have the city in uproar this year at the shortness of their skirts and the bareness of their legs - a uniform dreamt up by a bureaucrat in a love hotel if ever there was one. Only the schoolboys seemed to be elsewhere. Perhaps they were playing sado-masochistic computer games, or reading manga, the ubiquitous Japanese comics that lend new meaning to the term "strip" cartoon.

I had never seen such crowds. Central stations like Shinjuku are used by two million people daily. At rush hour the halls and stairways were a blurring frenzy of salarymen and secretaries, shoppers and school-children, pressing lost tourists into corners. Branching out into a warren of passageways, underground arcades and halls, this station could take an hour to cross, even if you did know where you were going.

So love was eclipsed by Tokyo's second face: overcrowding. Only in Tokyo could people sleep in capsules, like bees in a beehive. Capsule hotels imply lack of space but also modern urban technology. I wanted to sleep in one.

There were no English signs to go on, only instructions from a budget guide book. I descended from the world of neon and crowded sushi bars into a windowless empty hall that smelt of cleaning polish. At the lobby I stood nervously at the edge of a carpet while a receptionist gestured frantically at my shoes. Step one: take them off.

The hotel was a male sanctuary, an overflow from the streets outside. Men in dressing gowns sat about quietly in lounges, samurai warrior-style, with no buttons but powerful belts. I was given a numbered key. What? Was I really expected to squeeze into that tin box?

Actually that was the locker. But the capsules themselves were barely larger. Made of fibreglass with inbuilt TVs, they were stacked grimly one above the other along narrow corridors like monastic cells. Step two: take an evening bath.

At this point, things got very Japanese; a steamy room in which naked men sat on tiny benches, lathering and dousing themselves. Luckily they were too polite to stare at the white, hairy foreigner.

After the private soaping, I was supposed to sink into the mammoth hot bath that filled the centre of the room (after rinsing off the soap, of course. Failure to comply with this first law of bathing etiquette is considered grounds for ritual disembowelment. Bathing is taken seriously in Japan).

I had a great bath but a shocking night's sleep. Crawling into my capsule, I pulled down a blind and lay in darkness, surrounded on three sides by the muffled sounds of snoring, farting, and groaning from pornographic videos. It was Sunday. "Sunday have free adult video service," had been the receptionist's only words of English.

Yes, Tokyo is world capital of the art of packing things into small spaces. Bonsai trees were the opener which have now led to cameras and mobile phones the size of chrysanthemum petals. And you thought Japan was expensive? Cameras here are half the price of their equivalents back home.

Eating also takes place in unimaginable smallness. Sushi-by-conveyor- belt is one way of packing customers beside narrow bars rather than wasting space on tables and aisles. It, too, comes amazingly cheap, at around 80p a plate. As for noodle bars, even in opulent Ginza you can find yourself in front of steaming bowls, with dainty girls slurping noisily at your elbow.

Tokyo has always been crowded, even if its centre has shifted around over the years. Ginza became the city's showcase after Japan opened its doors to the world in 1868. In recent years, booming commercial areas like Shinjuku, Shibuya and Ikebukuro have sprung up around rail junctions.

But the old shitamachi, or downtown - Ueno and Asakusa in the north - still have a different atmosphere. I found streets here faintly shabby, with lines of tiny stores and local people slurping noodles. Men with flannels coiled round their heads shouted the price of crab in Ueno fish market, and local tramps had established a village of tarpaulin tents in the park.

The hey-day of the shitamachi passed away with the devastating Tokyo earthquake of 1923, in which nearly 150,000 died. But for a glimpse of old Tokyo I dropped in on the Shitamachi Museum in Ueno where a neighbourhood has been reconstructed, including wooden phone boxes, rickshaws and rickety houses with sliding partitions. The spirit of the capsule hotel was born in those narrow wood-paved alleyways.

If lack of space is the second face of Tokyo, tradition is the third. For my next night I chose a ryokan (Japanese inn), all futons, sliding partitions and tatami floors. The Kimi Ryokan was the cheapest in the whole of Tokyo - I paid less than pounds 20 for a single room - and no Japanese would have been seen dead in it. But it introduced me to 2,000 years of civilisation.

For like London, Tokyo has been an imperial city. But unlike London, there is no equivalent to the Royal Borough of Kensington and Chelsea, no Mall, no royal parks. There is just a single, isolated imperial palace in the centre of town. The map of Tokyo's underground network is designed round the palace like stars round the sun.

But approaching it on a murky, rainy Saturday afternoon did not feel like walking into the sun. Suddenly the crowds of beautiful people were gone. The great grey boulders of the wall round the imperial gardens were stained wet. Swans sat on the black waters of the moat.

Menacing or a secret pleasure garden? Hard to say, but a sudden explosion of trees gave hints of the latter. And what trees: these were Bonsais in reverse, delicate and wiry yet not confined to a flowerpot. A rolling lawn, smooth as paper, was dotted with spiney pine trees from a scroll painting.

All entrances to the inner garden were guarded by polite guards. The grandest entrance, the Nishu-bashi Bridge over the moat, could only be viewed from a distance. But behind the bridge, rearing up from behind trees in the rain, I caught a glimpse of heavy roof-tiles and upsweeping eaves - the inner sanctum of the palace itself.

But if the emperor was inaccessible to tourists, traditional performance arts such as Kabuki and Noh were less so. Down the road from the palace, in Ginza, is old Tokyo's answer to the Karaoke bar: the Kabukiza, or Kabuki theatre.

I had been advised to choose Kabuki rather than Noh on the grounds that Noh was dull and obscure and Kabuki action-filled and easy. Still not convinced I'd manage four hours, I bought a ticket for a single scene and pounds 2.50 got me a seat on the balcony. A stream of geisha girls with white masks and pink kimonos sat on the floor against a gilt backdrop. Two characters with high-pitched voices joined in an interminable dialogue. Inexplicable shouting from the audience burst out periodically, as if this were a Punch and Judy show. Action-filled and easy? Luckily a visit to a Noh performance was not on my agenda.

My search for tradition again took me to Ueno, where the National Museum commands the park. The main wing dates to the 1930s, the height of Japanese militarism, and its glowering eaves and monumental tiled roofline present a sinister profile. But inside I loved the costumes of the Samurai, the fighters who served Japan's feudal lords into the last century. With short, wide sleeves and no buttons, these were the model for today's Japanese dressing gowns.

And up in the heart of Akasusa is one of Tokyo's holiest temples, the Senso-ji shrine. There happened to be a Sunday event taking place, involving crowds of Shinto youth in short tunics and pouch briefs, with cloths squeezed between the buttocks, heaving huge wooden litters about. A middle-aged woman squatted to get a photo of one young man from pouch-height. The temple itself was a frenzy of drum beating and coin-throwing as worshippers jostled before the altar.

Did any of that traditional atmosphere survive in the real streets? Beyond Ueno, in Akasusa, I walked past tatty amusement arcades and old biscuit makers, then ducked into a tiny wooden restaurant where men sat along low benches under a nicotine-stained ceiling. The walls were covered in menu details like pages of manuscript. Guests slurped at clear soups of seaweed and fishballs, while bowing waiters rushed to my assistance. My soup cost pounds 2.

But enough with tradition. I now turned to the fourth and final face of Tokyo: the modern, the high-tech and the beautiful. On my last night I stayed in the Park Hyatt, one of the finest modern hotels in the world, filling the top 14 floors of Kenzo Tange's Shinjuku Park Tower. After a deep, private bath, I sat in my Samurai warrior dressing gown admiring original Japanese artworks on the walls and views spanning the murky width of Tokyo from the sea to Mount Fuji.

More evidence of Japan's unique talent for technology could be found in display rooms of the country's mighty corporations. I visited the Sony centre in Ginza, to test out the latest electronic appliances. Forget rainy views of the imperial palace: try instead a Sony Watchman, a glorified pair of sunglasses in which the eye pieces are tiny video screens. Soon we will all be wearing them.

Gadgetry and shopping are the engines of this colossal city. The vast department stores of Ginza, like Mitsukoshi and Wako, with uniformed lift attendants warbling sweetly face-to-the-wall, are palaces of exquisite packaging. In the food hall, even potatoes were gift-wrapped. Every time I raised an eye, high-pitched irrashaimases! chirruped from all directions. The fourth face of Tokyo, in its way, was every bit as charming as the first. Japan Fact file Getting there The author flew as a guest of Virgin Atlantic, which flies non-stop from London Heathrow to Tokyo six times weekly, with convenient departure and arrival times at both ends. For reservations, call 01293 747747. Fares for October/November are pounds 1,053 return in economy.

Budget tickets, via other European cities, can be obtained from around pounds 500. Try Worldwide Flights (0171 388-6000) whose flights on Aeroflot via Moscow cost pounds 517 return.

Accommodation The Kimi Ryokan (0081-3-3971-3766), near Ikebukuro station, has single rooms for just 3,500 yen (pounds 18). Doubles go up to about 7,000 yen (pounds 30). Bathrooms separate.

The Park Hyatt Tokyo (reservations in the UK: 0345 581666) has a supersaver rate of 33,500 yen (about pounds 175) for a double room; standard rates are 46,000 yen (about pounds 240). Add 10 per cent for service charge. The superb Japanese lunch in the ho tel's Kozue restaurant is well worth trying for the combination of food and views; reckon on about pounds 40 a head.

Getting around A taxi to or from Narita airport will cost around pounds 130 (no kidding). Take the limousine bus or the Narita Express train straight into central Tokyo (both about pounds 15). In town the circular Yamamoto train line is most convenient for linkingthe main centres. Single rides cost about pounds 1. There is also an extensive underground system.

Packages The Japan Experience (0703 730830) specialises in city breaks and tailor-made holidays to Japan. Explore Worldwide (01252 319448) offers cheap overland trips.

Information The Japan National Tourist Organisation in London can be contacted on 0171 734-9638. Lonely Planet publishes a reasonably good city guide to Tokyo for pounds 6.95.