Paris Charles de Gaulle Airport (CDG)

Three buildings and the letters that matter

Terminal 1 is the round one — a concrete drum whose gate satellites are reached through underground tunnels — and it takes most international carriers outside the Air France alliance. Terminal 3 is the small flat building at the far end, used by low-cost and charter flights and quick to clear. Between them sits Terminal 2, which is not one hall but seven, lettered A to G along a single long axis, with Air France and its partners across most of them.

The letters repay learning, because they do not behave alike: the long-haul halls sit at one end of the axis, the European ones next door, and one of them cannot be walked to at all. Terminal 2G is a detached satellite for short regional flights, served only by its own shuttle bus from the hall beside it. Everything else — terminals, car parks, stations — is linked by CDGVAL, the free automated shuttle that loops the site and is the only sensible way to change buildings.

Into the city: the RER B and the flat-fare taxi

The airport has its own railway station under Terminal 2, and the RER B runs from it into the centre, calling at Gare du Nord, Châtelet and Saint-Michel before carrying on south. A second RER B station serves Terminal 3 and, by shuttle, Terminal 1. The line is a working commuter railway rather than an airport express, so it stops often and fills at the wrong hours — and it is still the only link that ignores the motorway entirely.

The rank outside each terminal runs on a regulated flat fare set by prefectural decree: one price for addresses on the Right Bank, another for the Left Bank, the same by day and by night and in both directions. It covers a direct run only, so a requested stop on the way hands the journey back to the meter. The fares are posted at the rank, licensed Paris taxis are the cars that honour them, and touts working the arrivals hall are not.

The border queue that decides your arrival

Arriving from inside the Schengen area there is no passport check: you walk from the gate to the belts and out. From outside it you clear the external border first, and that queue, not the taxiway, makes an arrival long or short. Eligible biometric passports use the PARAFE automated gates, which read the chip and the face and move far faster than the staffed desks; who qualifies, and what a nationality needs before boarding at all, belongs to the entry rules for France.

Expect biometric registration on a first crossing of the external border, taken at a kiosk or by an officer, and expect it to add time later crossings do not. Departures have their own rhythm: the long-haul wave builds in the morning, the European one in the late afternoon, and both stretch the security lines. Check-in for intercontinental flights closes earlier than most travellers assume.

The TGV platform: the layover that skips Paris

Below the RER platforms under Terminal 2 is a main-line station where high-speed trains call, and it is the thing this airport has that no other French airport does. You can land here and be on a train to Lyon, Bordeaux, Lille or Brussels without entering the capital at all, which makes Charles de Gaulle a national interchange rather than a Paris one — a useful inversion in a country whose rail network radiates outward from Paris.

Whether a layover is long enough to leave turns on the border rather than the clock: connecting within Schengen you never cross it, connecting from outside you enter the country and clear the border again on the way back. A cluster of hotels stands at Roissypôle, a shuttle stop from every terminal, and they are the default for a pre-dawn departure or a broken connection. Paid lounges with showers and day rooms make a long wait usable.

Onward: car hire, and the trip across to Orly

Car hire desks are grouped at Roissypôle, the return lanes in the same complex and a shuttle ride from the terminals rather than a walk — worth building into the drive back. A car collected here suits Normandy, Champagne and the north; driving one into central Paris is the classic mistake, since the low-emission zone and the parking make the train the better choice. Orly sits across the city with no direct link: two rail legs through the centre, or a taxi under its own posted fare.

Practical: connectivity, money, bags and assistance

Connectivity is easiest solved before you fly, since an eSIM that activates on landing saves hunting for a counter at the moment you are trying to find a platform or a driver. Cash machines are spread through all three buildings — use a bank-branded one, decline the offer to charge you in your home currency, and leave the rest to the guide to money in France.

Two counters catch people on the way home. Tax-free refunds for eligible non-EU residents are validated before the goods disappear into a checked bag, so the refund desk comes before check-in rather than after security. Left luggage is landside, so a bag stored while you go into town must be collected before you clear departures; assistance for reduced mobility is booked through the airline.