I could spend the time doing the research, but I bet someone else has already done it.
What, if any, are the restrictions when coming from the US, changing planes in Amsterdam or Frankfurt or London; in route to a location where US citizen admittance is allowed.
I was give this link by a good RS poster: https://www.iatatravelcentre.com/passport-visa-health-travel-document-requirements.htm
Its the organization that tracks all the rules for the airlines to use. For my sample trip from the US to Hungary with a change of flight along the way
UK: Yes
Turkey: Yes
Frankfurt: Could not get a yes
Netherlands: Yes
In addition I got this off the webpages of the airports:
Can I still transit/connect through Heathrow?
Many passengers are taking flights that connect through Heathrow to their onward destination. We would like to reassure you that you are still welcome to transit through Heathrow; but will need to bear a few things in mind when preparing for your flight.
If your departing flight is on the same calendar date as your arriving flight and you have been issued a boarding pass for your onward flight, you will be free to transit/connect through Heathrow without having to clear Immigration.
https://www.heathrow.com/customer-support/faq/coronavirus-covid-19
Can I transfer at Schiphol?
Whether or not you can transfer at Schiphol depends on your destination and on the country you are travelling from. First of all, you should check the travel advisories on Netherlandsworldwide.nl. Travelling within the European Union (EU) and the Schengen Area is currently permitted, but this situation may change if the number of COVID-19 cases starts to rise again. Are you travelling from outside of Europe and transferring at Schiphol? Then take a good look at the travel advisories that apply to the country you are coming from, the Netherlands and the destination country.
[clear as mud]
https://www.schiphol.nl/en/page/coronavirus-and-schiphol-frequently-asked-questions/
James, I can speak to the Amsterdam connection as we've flown in and out of the airport a few times since the COVID situation began. Yes, American citizens traveling on a US Passport can connect at AMS, but you will have stay AIRSIDE. Currently, US citizens cannot enter the Netherlands. To meet the criteria to enter the Netherlands (as outlined in the Schiphol statement above), you'd have to be traveling on an EU passport, be from one of the "EU-approved" countries (the USA is not), have an EU Visa, or be an "essential traveler" with pre-arranged clearance. Of course, these restrictions/rules could all change tomorrow. (For example, we're flying to Copenhagen this weekend but had to get an "exception" to the 6-day-stay minimum in Denmark).
Schiphol is relatively quiet these days, with minimal stores open and very decreased traffic. In June, my wife flew back-and-forth to the USA using her Dutch Visa to reenter The Netherlands on her return. No other Americans were in line at passport control or at the baggage carousel. There were US citizens on her return flight from ATL, but they were all connecting, many heading to the Far East (or other "approved" destinations).
Disappointedly, COVID checks at AMS have been quite inconsistent - frankly, pretty lax in our travels through the airport. That may change as recently we've seen an increase in the number of in-country COVID cases. Unfortunately, the Netherlands has recently "hit the quarantine list" for a few countries - like the UK - so it seems the rules of entry/exit seem to change daily. (There goes our October weekender to London...)
Ron, thank you. It all seemed a bit sketchy to me so I booked through Istanbul. Lets see how that works out.....
