¿Adónde vas a ir "por" / "para la" Navidad?

Question

LanguageZen asked me to translate

Where are you going for Christmas?

and said that the correct answer is:

¿Adónde vas a ir para la Navidad?

According to SpanishDict's article on "Por" vs. "Para",

Para is used to talk about purpose, recipients, opinions, destinations, deadlines, and standards.

And

Por is to talk about duration, reasons, motives, emotions, exchanges, mode of communication or transportation, and subsitutions.

This doesn't really help me because I could see it either way:

• The reason you're going anywhere to begin with is Christmas, so I should say "por".
• The purpose of your trip is to celebrate Christmas, so I should say "para".

Is "por" also correct then, and if not, why?

Answer 1

Both por and para are OK in different contexts. There are differences between them, and probably these vary among dialects as well. These are all valid sentences:

Para Navidad reservé en un buen restaurante.

(also works if you say para esta Navidad or para la Navidad). This means you made a reservation in a nice restaurant in order to celebrate Christmas there (intent).

Por Navidad estaré fuera de casa.

This means you will be away from home because of Christmas (reason) or during Christmas (duration).

Regarding the question itself, I would interpret the alternatives as:

¿Adónde vas a ir para (la) Navidad?
"Where do you intend to spend Christmas?"
"Where will you go in order to celebrate Christmas?"

and

¿Adónde vas a ir por (la) Navidad?
"Where are you going during Christmas?"
"Where will you be while Christmas takes place?"

You can see the difference between these is not great. Moreover, you expect people to do certain things on Christmas, so the question need not be precise. If you say you'll be spending Christmas at a given place, it's assumed that you'll be there celebrating Christmas, not hiding or whiling away your time.