Schengen visa clarification: can I travel to other Schengen countries?

Your mode of transportation doesn't matter. Taking a plane within the Schengen area does not count as a new entry, you often doesn't even have to show your passport when flying within Schengen (but that depends on the airline - and I believe you are required to carry some ID).

can I travel to other Schengen countries?

Yes

I'm traveling first to Austria; then I booked a flight to Paris, France. Is that possible or should I take only trains or vehicles to travel since my visa is only a single entry? Can I fly to other Schengen countries with a single entry visa?

Taking internal flights within the Schengen area is fine on a single entry visa but you need to avoid using flights with a stop/layover outside the area to travel between two locations in the area as once you leave the area you will not be able to re-enter.

Should I travel to the country that issued the visa? I'm going backpacking through Europe and I don't know my longest destination or my actual destinations, to be clearer.

You are supposed to apply for the visa to (in order of precedence)

• The country that is your main destination.
• If no main destination the country in which you will spend the most time
• If no country in which you will spend the most time the country where you will enter the area.

Once you have the Visa it is normally valid for all countries in the area (limited territorial validity visas exist but are rare), but lying on a visa application is grounds to annul a Visa. Sometimes people lie about their itineries to "consulate-shop". Therefore border control sometimes get suspicious when people turn up with a single-entry visa from a different country.

So you should be prepared to demonstrate that you applied to the correct consulate for your trip and that you did not lie to them about your itinerary.