Мы вместе вспоминаем, как когда‑то ездили к морю всей семьёй.

Together we remember how we once went to the sea with the whole family.

Breakdown of Мы вместе вспоминаем, как когда‑то ездили к морю всей семьёй.

• ездить: to go
• к: to
• море: the sea
• мы: we

Questions & Answers about Мы вместе вспоминаем, как когда‑то ездили к морю всей семьёй.

What exactly does вместе modify here? Does it mean “together we remember” or “we remember that we went together”? Could it be placed somewhere else in the sentence?

In this sentence, вместе most naturally relates to вспоминаем:

• Мы вместе вспоминаем… = We are remembering together… (several people are recalling something jointly).

It can also be moved, with slight shifts in emphasis:

• Мы вспоминаем вместе, как когда‑то ездили к морю всей семьёй.
  Still: We remember together…; вместе is visually closer to вспоминаем, but the meaning is the same.

If you wanted to emphasize that the trip was done together, you’d usually show that with всей семьёй (or similar), not by moving вместе:

• Мы вспоминаем, как мы вместе ездили к морю.
  Now вместе clearly belongs to ездили: how we traveled together to the sea.

So, in your original sentence, вместе describes how you are remembering (together now), while всей семьёй describes how you traveled then (as a whole family).

Why is there a comma before как: вспоминаем, как когда‑то ездили…? Is как here “how” or “that”?