Learn German: Wohin gehen wir heute? - Where are we going today?

Wo asks about a fixed location (meaning "where at?"), but wohin asks about a direction or destination (meaning "where to?"). Because the verb gehen (to go) involves movement toward a destination, we must use the directional word wohin.

In English we say "are we going". Why is there no word for "are" in the German sentence?

German doesn't have an "-ing" form (continuous tense) like English does. The single present tense verb gehen covers both "go" and "are going". Trying to translate "are" by saying sind wir gehen is a common mistake for English speakers, but that structure simply doesn't exist in German!

Why does the verb gehen come before the subject wir?

In German questions that start with a question word (a "W-word"), the conjugated verb always takes the second position. The subject usually follows immediately after it. So the structure is Wohin (Position 1) + gehen (Position 2) + wir (Position 3).

I sometimes hear people put hin at the end of the sentence. Can I do that here?

Yes! In everyday spoken German, it is very common to split wohin. You can completely rewrite this as Wo gehen wir heute hin? with wo at the beginning and hin at the very end. Both versions are perfectly correct and mean the exact same thing.