Because I was heading towards Mount Fuji with two people who were literally going out of their way to smooth my progress around Japan. Half-an-hour earlier they had had no intention of driving up the long and very winding road towards Japan's most sacred mountain. The helpful couple, who spoke good English, would presumably rather be elsewhere than aiming for Fuji Fifth Station, where the road ends and the climb begins. But, I fretted from the back seat as the driver negotiated yet another hairpin bend, they were much too polite to say so.
The couple had been persuaded to change their plans and take off up a lengthy cul-de-sac not from any subterfuge on my part, but because of my quaint Western habit of hitch-hiking. An hour earlier, late in the evening, I had arrived in the town of Fuji-Yoshida. The last bus to the base station had long since gone. The only alternative I could see to the 12-mile trudge to Mount Fuji's base camp was to thumb a ride part of the way. But this being Japan, the gracious couple who were driving home through town when they saw me felt obliged to take me miles out of their way to the end of the road. And I felt anxious at taking advantage of their good nature - but not so much that I was willing to say "oh, just drop me off here".
Nocturnal travel fits snugly into any budget journey around Japan. I was cramming as much of the nation as I could into a week of high-intensity experiences. Seven days is the duration of one of the world's great travel bargains, the Japan Rail Pass, and I was determined to make the most of my pounds 150 investment.
The easy part was Tokyo, before my wanderings began. The capital has a reputation for high energy and high expense. Energy, most certainly: at Tsukiji Fish Market (see page 8) I got so caught up in the frenzy of 20th-century commerce that I nearly bought a whole tuna (now that's what I call excess baggage), and later I was treated to a glimpse of the 22nd century at the Sony Building. But I quickly learnt that you need no platinum credit card to survive in 21st-century Tokyo. Low-cost accommodation is easy: if you prefer not to turn Japanese in your capsule hotel, you can check into a cut-price hostel. The next essential, eating, is easily negotiated thanks to the ubiquitous bowls of ramen noodles. And the pleasures of city life are either free (such as the jaw-dropping view of the city from the top of Tokyo Metropolitan Government Building) or cheap (immersion in an onsen, communal bath, at the end of the day).
Sooner or later, though, you yearn to break away from the megalopolis that is greater Tokyo city. Six hundred kilometres should do it: that is the rail distance from Tokyo to Hakodate on the island of Hokkaido, a serene, historic port city that you can barely believe is in the same country as Tokyo. Perhaps that's because the journey involves a trip through the world's longest tunnel on land, between Iwate and Inchinohe, and the longest underwater tunnel - a burrow linking the islands of Honshu and Hokkaido, which is even longer than the Channel Tunnel. The trip involves a relay of trains, which seem cleverly designed to connect with just enough time to buy another bowl of ramen at the station.
You could easily while away a week on Hokkaido: taking the plunge at the hot springs resort of Noboribetsu, then taking the free tour of the Sapporo brewery in the island's capital.
Away from the big cities, accommodation at minshuku (small, family-run B&Bs) and ryokan (traditional inns) is reasonably affordable. Only the ever-practical Japanese, though, would come up with the concept of goronto seat. This translates as "reserved carpet space" on overnight trains, which means rail pass holders can legitimately kip on the floor all the way from Sapporo to Tokyo for nothing. And, being Japan, you can be assured that the carpet is freshly vacuumed and wildlife-free.
Goodness: Amsterdam already? The Japanese unashamedly copied PJH Cuypers' masterpiece from the Dutch capital, the Northern Renaissance-style Centraal Station, and it is well worth admiring while you change trains in the capital. So, too, is the way that the Shinkansen (Bullet Train) is despatched: in a little bit of ballet, the driver ceremoniously points at the clock and then the signal before he guides his train away at the appointed second. (Women train drivers remain an exceedingly rare species in Japan.)
The Bullet Train was an icon of the Sixties: the first ran on the Tokyo- Osaka line on 1 October 1964, and this stretch of track remains the spine of the network. The fastest trains cover the 553km in two-and-a-half hours; these are 300kph Nozomi "super expresses". But even the ordinary Bullet Train services travel at speeds of which British train drivers can only dream. As you glide along through the cityscape and countryside, the nation is revealed in fast-forward.
Part of the art of seeing Japan is knowing when to slow down, which is why, at Otsuki, I had transferred to the local train to Fuji-Yoshida. The unadvertised connecting lift took me halfway up the mountain to Fuji Fifth Station. Here, close to midnight, the meticulously benevolent couple observed that I was not properly prepared for an ascent of the holiest peak - and donated a baseball cap.
By 4am, when I was still shuffling up the volcanic shale, I was glad of the headwear. I was also grateful for the convenient way in which catering outlets appear in the strangest places: every hour or so on the six-hour hike, a mountain hut appears from out of the gloom, dispensing warmth, coffee and, inevitably, noodles to the weary hikers.
The traditional reward for scrambling to 3,776 metres - equivalent to a good-sized Alp - is the awesome view from the summit rim at sunrise. All that happened when I was there at dawn was that the fog changed from dark grey and impenetrable to light grey and impenetrable. "A wise man climbs Fuji once," goes the local saying. "A fool climbs it twice."
But there was no time to loiter in the hope of fine weather: after retracing my furrow down the mountain, I still had to reach Kobe, a harbour city as magnificently located as Sydney and miraculously resurrected after the Great Hanshin Earthquake of a decade ago. Then it was back to the bewitching Imperial city of Kyoto, to savour every moment among the temples and parks and palaces. The crafty traveller times the Japan Rail Pass to expire just after the journey to the airport. Would you believe it: the train from Kyoto to the artificial island bearing Kansai airport was late. Only five minutes, mind - not enough to cause any stress.