Could someone explain Schengen and Non-Schengen?

Could someone explain Schengen and Non-Schengen? I assume this has something to do with passport control etc.

How does it factor into connecting flights? FOr example, if I fly AF from IST to CDG with a connection to AF from CDG to JFK, am I going through immigration in Turkey and again in Paris, or in only one, and if so, which one?
What about luggage? Is it checked through to is it picked up at CDG and checked again?

Thanks.

The Schengen countries are Austria, Belgium, Denmark, Finland, France, Germany, Iceland, Italy, Greece, Luxembourg, Netherlands, Norway, Portugal, Spain and Sweden.

If you are travelling Schengen to Schengen, you will not be subject to immigration, but you will be subject to customs. However, you may still have an ID requirement for check-in or mandated by the destination country.

If you are travelling Schengen to non-Schengen or vice-versa, directly, then you will be subject to immigration and customs at the destination.

If you are travelling Schengen to non-Schengen with a change in a Schengen country, then you will clear outgoing immigration (if there is any) at the transfer point, and incoming immigration and customs at the destination.

If you are travelling non-Schengen to Schengen with a change in a Schengen country, then you will clear incoming immigration and hand luggage customs at the transfer point, and checked luggage customs at the destination.

If you are travelling non-Schengen to non-Schengen with a change in a Schengen country, then, assuming the airport allows it and you remain airside, you will clear both customs and immigration at the destination.

So, for IST-CDG-JFK, the last option will apply.

Schengen is the term for a multilateral agreement on waiving passport and border controls between countries of the EU. There are only controls at the Schengen borders, e.g. in AMS when coming from NYC. If you fly FRA-AMS, there is no passport control in AMS. For IST-CDG this is not relevant; as a special bonus of CDG airport you will have to go through security again anyway, since you have to leave the 'secure' area to change terminals . Your luggage will be checked through, that's no problem.

That's wonderful news, that I get to go through passport control and security a second time at CDG. Seriously, is it possible to stay airside on shuttle buses and avoid this traveling from terminal 2C to 2B?

For IST-CDG-JFK, this is only true if you choose to go landside. If you take the airside bus from 2E to 2C or 2F2, then you only go through security again, not passport control (although you may have to show your passport & boarding pass to go through security). Anyway, it's a realatively painless procedure either way, except for long lines at peak periods. But I can't ever remember waiting more than 5-10 minutes either way, which is much better than waiting times for security at ATL, JFK or LAX during peak periods. I've heard horror stories about CDG Terminal One, but T2 has always been very fast and efficient for me.

yes, there are shuttle buses between 2C and 2B. so you can stay airside.

No customs within the EU but, in spite of Schengen, customs controls between EU and Norway/Iceland. As for the UK and Ireland, well that's another story...

At least the UK is a non-Schengen country. Ireland as well I think.

Custom:
if your checked in bag has a strip with 2 small green borders it means you are inside EU so no Custom even if passing a Schengen to non Schengen 'line', e.g. Frankfurt to London or Frankfurt to Madrid.

Correct. The UK and the Republic of Ireland form a common travel area where passports are not needed to travel between the two.

I didn't think Iceland was in Schengen - or have they joined recently?

The basic principle one needs to understand is that Schengen vs non-Schengen is about Immigration whereas EU vs non-EU is about Customs.

There are EU countries that are not part of Schengen - the UK, Ireland and all the new EU members.

There are non-EU countries and territories that are part of Schengen - Norway and the Faroe Islands are members now, Switzerland is due to join in the near future.

And don't even get started on the status of the Isle of Man and the Channel Islands...

Excellent summary.

In addition, for our US friends,

They used to have some sort of a common travel area with the other Nordic countries so they joined Schengen with everyone else (Norway, Denmark, Sweden and Finland).

Actually, you do need a passport to travel between the UK & Ireland. At least non-EEA pax do.

Of course it's a requirement in theory. I flew ATL-DUB-LCY over the summer and not once did any immigration official (American, Irish or British) ask to see my passport.

At DUB, I showed them my DUB-LCY boarding pass and was simply let into the country! And at LCY there was no immigration officer present.

Basically, I entered and exited Britain and Ireland undetected!