In Seoul we stayed in a tiny studio flat fourteen floors above the railway tracks snaking out of Seoul Station. Approximately the same distance below street level, the bullet-fast new subway trains zoom out to Incheon Airport. And in between these poles spreads a vast neon-lit city of white skyscraper blocks interspersed with tropical wooded hills. Of the glittering Asian cities we passed through, Seoul is the best. It avoids the catastrophic traffic of Beijing and the ruthless materialism of Hong Kong. It simply works, with cheerful efficiency, and it is not hard to see why it is home to the second biggest economy in Asia.

Apart from touring the Royal Palaces (poignant, respectfully preserved) and going up the N Seoul Tower, we did just one tourist excursion. Apparently only Europeans have any interest in this one – the Chinese, Japanese and Singaporeans visit exclusively for the shopping (see below….). It was a guided bus trip up to the DMZ – the 3-kilometre wide de-militarised strip between South and North that slices straight across the Korean peninsula. It was fascinating, and deeply weird that this dividing line is treated as a visitor attraction, apparently by both sides. First we toured the eerily deserted Dorasan train station that will – some day – be not the last stop on the line up from the south but the first on the journey north. Until that happy day the departure boards show only one destination, Pyongyang, with no times or dates ventured. Next we put our coins in the slots of the powerful observation telescopes and trained them on the barbed wire and gun posts three kilometres away, and on the settlement just north of the line that S Koreans call Propaganda Village. The houses look solid and the fields well tended, although it’s said that no one actually lives there. The lights all go on at the same time every night. In the zone separating the barbed-wire lines, nothing stirs. It’s too heavily mined for anyone to venture into, although several species of otherwise endangered birds and mammals thrive amongst the tangled vegetation.

The culmination of the trip was an underground excursion into one of the three spy tunnels penetrating under the DMZ – dug by the north and discovered before any invasion of the south could be launched. We put on hard hats and hunched over to descend several hundred metres of steep rocky tunnel. At the bottom was a heavily barred door, through a slit in which another armoured door could be glimpsed three metres away. Beyond the second door lies a third, we were told – the closed gateway to the armoured north. It was cold, claustrophobic, and deeply creepy. No hardship at all to turn tail and make the panting ascent to the sunshine once more.

Our little apartment lay just across the 6-lane highway from a giant shopping mall, housing outlets for every brand from Adidas to Zara. The football-pitch acreage of its food store was open 24 hours, so we were able to browse the sushi or salad aisles at 3 a.m. Not that we needed to. Food and restaurants are big in Korea. HUGE. I had plenty of kimchi, thanks.

And that shopping? There are more and bigger and shinier malls than I have ever seen. It was hard to credit that so many designer handbags, pairs of sunglasses and cosmetics displays could be collected in one city. I bought nothing, save a carrier bag in one of the street markets. There is such a thing as too much choice.

My favourite time in all Seoul was discovered in a seedy block five minutes’ walk from ours, under a neon sign saying ‘Silloam Spa’. It might have been a love hotel or even a brothel, but in fact it was five floors of heaven. The Koreans adore a spa, and so do I. Although the interior décor was brown plastic and fake foliage it was sparklingly clean, a labyrinth of miraculous sauna chambers offering heat and chill and pumped-oxygen or charcoal-filtered air, and jade fountains and heated clay beds, rest rooms and jacuzzi pools and even dormitories on the top floor where you can sleep overnight if you wish. I had the best non-sleazy massage of my life, and found the segregated women’s areas nakedly relaxed and even sisterly. (Not a word I often reach for.) All this, for a maximum stay of 12 hours, for $8.

Five days in Korea was far too short. I didn’t even get to Nami Island, let alone down to Busan or the east or west seas. Must come back again, soon.