Frankfurt layover: is there time to see the city?

Under 5 hours: stay at the airport. Passport control, the train both ways and security again eat most of it, and a delay on the way back costs you the flight.

5 to 6 hours: possible if you arrive and leave within the Schengen area, or if you travel with hand luggage only and passport control is quick. Plan about 1 to 1.5 hours in the city, not more.

6 to 8 hours: the safe range for most travellers, including non-Schengen connections. 2 to 3 hours in the city.

8 hours and more: a relaxed half day: the old town, the river and a meal.

To leave the transit area you must be allowed to enter the Schengen area. Many nationalities can enter without a visa, others need one. If you need a Schengen visa and do not have one, you cannot go into the city, however long the layover is. Check before you travel.

If your checked bag is booked through to the final destination, you do not have to collect it. If it is not, you need to collect it and either drop it again or store it; ask your airline at the transfer desk.

Take the S-Bahn line S8 or S9 from the regional station under Terminal 1 (signposted Regionalbahnhof, not the long-distance Fernbahnhof). It runs about every 10 minutes and reaches Frankfurt Hauptbahnhof in about 12 minutes; Hauptwache, in the middle of the old town, is a few minutes further on the same train.

A single ticket costs about 6 euros from the machines on the platform; buy one for the way back too, or a day ticket if you plan more rides. From Terminal 2 take the free SkyLine train to Terminal 1 first.

Count backwards from your departure:

1. Be back at security 2 hours before departure for non-Schengen flights, about 1.5 hours for Schengen flights. Frankfurt is large, gates can be 20 minutes' walk from security.

2. The train back plus the walk to the station: about 45 minutes, with a buffer for a missed train.

3. On arrival: passport control can take up to about 45 minutes when several long-haul flights land at once, then 15 minutes to the train and 15 minutes on it.

Example for a 6 hour layover with a non-Schengen arrival: 1 hour to get out and into town, 2 hours and 45 minutes back to the gate in total, leaves about 2 hours in the city.

Get off at Hauptwache. Everything worth a first look is within walking distance: the Römerberg with the town hall, the cathedral, the rebuilt old town between them, the river Main with the Eiserner Steg footbridge and the skyline view from the other bank. A loop through these is about 2 to 3 kilometres, an hour at an easy pace, longer with a coffee or an apple wine in Sachsenhausen.

With more time, the riverside museums on the Sachsenhausen bank or the view from a skyscraper deck are the classic additions. On Sundays and public holidays most shops are closed, the river and the old town are not.

Guided tours start at fixed times, and on a layover you cannot wait for one. CuriFox is a free app that builds a walking loop from where you stand, with the length you pick: 1 to 2 km for a short stop, more if there is time. At every stop there is a short story about the place in front of you and a small riddle, in English or other languages. Start it when you step out at Hauptwache and end back at the station.

It needs mobile internet; many non-EU SIM cards roam expensively, so an eSIM or the airport Wi-Fi to download the app first helps. More about the free walk: Free walking tour Frankfurt by app and self-guided walking tours in 16 German cities.