5....netherlands-belgium-luxemborg-germany-france.....1979 driving....

My wife and I used Basel as our base to do as many international border crossings in a day as we could. For no real reason other than to say we did it, bare we mind we come from an island country with no borders so such a thing is a novelty. Each time we crossed over we made sure we got out of the car, bought some chocolate, had a coffee, went to the loo, took photos anything to validate it. CH-D-FR ad nauseum.

We gave up after about 18 crossings. The novelty wore off quickly.

I've done four in a day more times than I can easily remember in the normal course of business. Three in a day I probably couldn't even count.

Five in a day (with actual work to do in each of those) is a little more difficult to recall, but I've done it a few times most recently just 3 weeks ago (India - UAE - Ghana - Algeria - UK).

Also, some years ago I did Switzerland - Liechtenstein - Austria - Germany - France - Italy with some friends but this was just a touristy trip with no real purpose other than to use our rail passes to go as many places as possible. I managed to get stamps from each of those except Germany as well!

I'm counting connections. I don't consider having visited a country until I actually get out into town, but for the purposes of this question, I would consider a mere stopover.

Driving does give one a better chance to actually accomplish something. In this instance, I think I recall doing Switzerland-Liechtenstein-Austria-Germany in one day.

I've had several sequences each lasting several days travelling without getting a real bed.

I've also had 6 international flights departing on the same day (AKL-SIN-CGK-SIN-CGK-SIN-NRT, yes 2 round trips to CGK with activities in SIN in between each arrival and departure).

Back to the original question, and all not counting repeats. 5 seems to be my limit.

3 in a calendar day too many times to count

4 within 24 hours - Italy (x2), Switzerland (x2), France, Vatican City

4 in a calendar day, a couple of times while bussing in Europe

4 in a calendar day flying - UK, Netherlands, Germany, Denmark
4 in a calendar day flying - Oman, UAE, UK, Spain
4 in a calendar day flying - NZ, Tonga, Samoa, USA
4 in a calendar day flying - Germany, Switzerland (x3), Luxembourg, Italy
4 in a calendar day flying - China (HKG) (x2), South Korea, Canada, USA
4 in a calendar day flying - NZ, Singapore, UK, Switzerland
4 in a calendar day flying - Germany (x2), Serbia, Swizterland, Tunisia
4 in a calendar day flying - NZ, Australia, Singapore, Maldives
4 in a calendar day flying - Brazil, Argentina, Chile, Ecuador

5 in a calendar day flying - USA, Barbados (x2), St Vincent, Trinidad & Tobago, Grenada
5 in a calendar day flying - Iran, Austria, Bosnia & Herzegovina, Croatia, Germany
5 in a calendar day flying - Algeria, Germany (x2), Slovenia, Kosovo, Austria
5 in a calendar day flying - NZ (x2), Australia, Chile, Paraguay, Argentina

I actually drove this in a single day (departed right after midnight):
Poland -> Czech -> Germany -> Switzerland -> Italy

Golden Triangle day was cool...Breakfast in Myanmar, lunch in Laos, and dinner (Cabbage and Condom restaurant) in Thailand.

Driving home from Pisa (Italy) to Amsterdam a few years ago.

Italy > Switzerland > Germany > France > Luxembourg > Belgium > Netherlands

I will routinely do three in a day for work:

Wake up in London, travel early morning to nearby European country A, meetings all day in European country A, travel to further European country B, sleep in European country B. Next day, meetings all day in European country B, travel home to London.

Same here... Usually do this (or the reverse order) about 4 times per year driving home to Milan from Holland.

I suppose on this route 9 countries should be easily possible with a route taking in Austria and Liechtenstein (purely to have done it). Possibly 10 or 11 countries within 24 hours could be possible by heading up to Denmark and starting in Slovenia.

Slovenia to Denmark via Liechtenstein and Luxembourg?!

Four countries:
BOM-DXB-SIN-MEL (stupid EK sale and my cheapness)

Three countries
SYD-SIN-KUL
BOM-SIN-MEL
REP-KUL-DEL
SYD-NRT-LHR
plus many more i can't remember.

Well, you wouldn't drive it by accident, but Google Maps thinks you could do it in 21.5 hours:

http://maps.google.com/maps?f=d&sour...:kolding&hl=en

Slovenia-Austria-Liech.-Switz.-Germany-France-Lux-Belgium-Netherlands-Germany-Denmark, to be precise. You might even be able to squeeze in Italy, Croatia and/or Sweden if you pushed it.

I've celebrated two new years eves, having crossed a time-zone on a cruise ship in 2008

starting from Zagreb, 24 hours according to Google Maps

I've done this by air, flying AKL-HNL on new years day.