Paris to Brussels
Two Capitals, Eighty-Two Minutes

Gare du Nord is the grand old gateway of northern Europe - a colonnaded 1860s facade crowned with statues representing the destinations its trains once served, Brussels among them. Brussels Eurostars depart from the main-line platforms under the great trainshed, not from the sealed upstairs terminal used by London trains: for Brussels there is no UK-style check-in, just ticket gates at the platform entrance. Scan your barcode, find your coach, and you are aboard.

Eurostar suggests arriving around 20 minutes before departure - enough for the gates and a coffee from the concourse. The station is on metro lines 4 and 5 and RER B and D, with Gare de l'Est a five-minute walk away if you are connecting from eastern France or Germany.

Within minutes of Gare du Nord the train threads the northern suburbs and joins the LGV Nord, the high-speed line that carries every London Eurostar and Lille TGV out of Paris. The speed builds quickly - cruising at up to 300 km/h - and the scenery settles into the wide, open farmland of Picardy: sugar-beet fields, poplar windbreaks and enormous skies, with the occasional wind farm turning on the horizon.

It is quietly historic country. The line crosses the Somme west of Saint-Quentin, and many of the names on the road signs - Arras, Albert, Péronne - are familiar from the First World War. The train does not stop (the lonely mid-field TGV Haute-Picardie station flashes past in a second), but it is worth knowing what you are crossing at five kilometres a minute.

Paris to the Belgian border is barely an hour of rolling farmland - the fastest history lesson in Europe.

South-east of Lille, at Fretin junction, the routes divide: London trains carry on toward the Channel Tunnel while your train swings east onto the Belgian high-speed line, HSL 1. Somewhere in the fields near Esplechin, France becomes Belgium - there is no announcement, no slowing, no checkpoint. The first hint is usually your phone changing network.

Both countries are in the Schengen area, so there is no systematic passport control in either direction - one of the quiet luxuries of this route compared with Eurostar's London services. Police and customs officers do occasionally walk the train, so keep your passport or ID card reachable rather than buried in the rack. The Belgian leg runs the high-speed line across the rolling Hainaut countryside before slotting into the classic network at Halle for the final approach to Brussels.

Brussels-Midi - Brussel-Zuid in Dutch, the same station wearing the city's two languages - is Belgium's biggest station and its international crossroads. Arrival could not be simpler: you step off the train onto an ordinary platform, walk down the ramp and out. No border desks, no baggage reclaim, no formalities of any kind.

The Grand-Place and the historic centre are about ten minutes away: any of the frequent mainline trains hops to Brussels-Central in a few minutes, or take metro line 2/6 towards the centre, or simply walk it in around twenty-five minutes. And Midi is a launchpad as much as a destination - Belgium's intercity network fans out from here, with frequent direct trains to Bruges, Ghent and Antwerp, typically in the thirty-minutes-to-an-hour range.

Eurostar works like an airline in one respect: every passenger has a booked seat on a specific train, and there is no such thing as turning up with an open ticket and boarding the next departure. Book ahead - the cheapest fares appear when sales open and climb as each train fills, with Friday and Sunday evenings the first to sell out. Standard covers most needs on an 82-minute hop; Plus adds space and a light meal; Premier is the business-class product with lounge access in both stations.

Interrail and Eurail passes are accepted, with the usual high-speed caveat: a compulsory paid pass-holder reservation, bookable through the pass operators' channels, with only a limited quota of pass-holder seats per train. On a corridor this frequent that quota is usually manageable, but reserve early in summer and around holidays. If the direct trains are full or the reservation feels poor value, itineraries with a change at Lille onto a TGV or local train are a slower but workable fallback.

If you have taken Eurostar to London, forget most of what you learned: that route involves UK border control and airport-style screening, with arrival recommended up to an hour ahead. Paris–Brussels has none of it. Boarding works like a domestic French TGV - ticket gates at the platform, a barcode scan, and aboard. Eurostar's own guidance is to arrive about 20 minutes before departure, and even that is generous once you know the station.

Luggage is refreshingly civilised too: two sizeable items plus hand luggage, no weight limit and nothing to check in - you wheel it aboard and stack it on the racks at the coach ends or overhead. Bikes and outsized items have their own rules, so check Eurostar's current policy for anything unusual. Carry your passport or national ID card: Schengen removes the queues, not the occasional onboard spot check.