I need immediate help about single entry Schengen visa

Hi,
I'm from Turkey and I got a single entry Schengen visa from German consulate.Can I follow this route? Turkey-Germany-Italy-Germany-Turkey.That is,can I pass between Schengen countries without any problem at all?(although it is a single entry one) Thanks in advance.

For immigration purposes the whole of the Schengen area is treated as one big area. So you going from Germany to Italy and back is no problem at all.

You are presumably flying from Germany to Italy and back? I ask that because a quick look at the map discloses no common boundary between Germany and Italy. If going at ground level ... car, train or coach .... what you cannot do is go through Switzerland ... because that is not yet in the Schengen area. That is, if you drive from Germany into Switzerland (ignoring any question about whether you need a visa for Switzerland), you will not be allowed to use your single-entry Schengen visa to go from Switzerland to Italy.

If you want to go at ground level then you will need to go via France or Austria.

John wrote:For immigration purposes the whole of the Schengen area is treated as one big area. So you going from Germany to Italy and back is no problem at all.

You are presumably flying from Germany to Italy and back? I ask that because a quick look at the map discloses no common boundary between Germany and Italy. If going at ground level ... car, train or coach .... what you cannot do is go through Switzerland ... because that is not yet in the Schengen area. That is, if you drive from Germany into Switzerland (ignoring any question about whether you need a visa for Switzerland), you will not be allowed to use your single-entry Schengen visa to go from Switzerland to Italy.

If you want to go at ground level then you will need to go via France or Austria.

I'm going by plane.IT's a touristic visa tho,nothing to do with immigration purposes.So,what is the result

Fine, given your destination is in the Schengen area, no immigration-style checks when you fly from Germany to Italy, or back.