Could it be national backpackers' day in Belgium? Teenagers - more than you would think such a small country could produce - all very big, all very hot, all with fridge-freezer-sized rucksacks on their backs - pile into the already crowded Brussels-to-Antwerp train.
If trains were Flemish paintings, this one would be Hieronymus Bosch's Inferno. By comparison, the fragrant London-Brussels Eurostar I had just left was the same artist's Garden of Earthly Delights. A new vision of paradise, munching Euro-sandwiches while travelling at 300 kilometres per hour across the flatlands of northern France, so that I can immerse myself in Flemish culture for a long afternoon, and get back to London well before the last tube.
It's not Bosch I'm chasing today, but another Flemish artist - Peter Paul Rubens. Which is why I'm on a train that seems to be sweating its way through the well-upholstere d Brabant countryside en route for Antwerp.
Within 45 minutes I'm gawping at the marbled opulence of Antwerp Central Station's neo-classical booking hall. I'm also, I have to admit, gawping at the people, the groups of elegant young locals sipping iced drinks at the pavement cafs. They're not Bosch's backpackers, and they're not even particularly Rubenesque. They're not by any Belgian painter that I know of.
The combined aromas of good coffee, hot waffles, fresh bread and chocolate fail to detain me. I head off down the Meir, Antwerp's main shopping street, taking note of all the typically Flemish retail outlets . . . CA, MS, Habitat, Bata, Tie Rack. When a market researcher approaches me, starting in Flemish then shifting to English, I start thinking I might as well have gone to Liverpool for the day.
The two cities have much in common. Both have been great ports, both have suffered periods of severe decline. Both are within a four-hour train journey from London. But Antwerp is once again a great port, number two in Europe. And I don't know of anywhere in Liverpool or any other British city where you can get such perfect chips as I've just bought for 60p from a stall. So there's an end of it.
I dodge off into a side street and immediately re-enter an attractive, distinctly Flemish city. Narrow streets opening suddenly into quiet, traffic-free tree-planted squares. Junk shops, spice merchants, ship's chandlers, exclusive jewellers and fashion shops. And cafs.
Still less than 15 minutes from the station, I reach the house in which Rubens lived and worked, which is now a museum dedicated to the life and work of the artist. Today is Monday. In Belgium, all public museums and art galleries are closed on Monday. Including my second objective: the Plantin Moretus Museum of Printing. I become a character in a Breughel painting: the peasant being kicked by his ass. Eurostar can take the pain out of European travel, but it's not a bad idea to plan.
All is not lost. There's still medieval and Renaissance Antwerp to explore. I follow a group of strolling mariachi players into a maze of narrow streets. All around people are eating, drinking, doing something creative, or watching something creative being done. I wonder what more could have happened in 1993, when Antwerp had its year as Europe's
At the heart of this maze
is the Grote Markt, a square surrounded by old Flemish buildings. Towering above the square is the cathedral. It is open, so in I go. I wander down the nave, and come face to face with the most bloodcurdling painting of the crucifixion I have ever seen. It's part of a triptych by Rubens, and its twin - the descent from the Cross - is a few feet away.
I'm gobsmacked. I've had my Rubens experience. Outside, Antwerp is shifting into early evening mode. The aromas are stronger, spicier, there's a different tempo to the street music. The caf and bar terraces are filling with noisier, even more stylishly dressed people.
Sadly, I've a train to catch.
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London to Antwerp from #163;69 return