Your departure location is up to you and should be based on convenience and your available options. For some, Vienna might be ideal, while others may prefer Berlin or Frankfurt. Prague often has expensive air tickets.
In our experience, we mostly fly from Vienna, choosing routes based on ticket prices, sometimes with layovers in Zurich, Madrid, or the US.Always ensure you have enough time to catch connecting flights.
We strongly advise against scheduling layovers of less than 4 hours in the US or Canada. Additionally, for connections in these countries, you will need a transit visa, which can be arranged in a few minutes but must be done at least 2 weeks in advance.
The visa is typically valid for a year or more, depending on the country. For EU connecting flights, a layover of 1.5 hours is usually sufficient.