The informal expression
a blast from the past conveys "something forcefully nostalgic."
someone you knew or something that existed in the past, that suddenly appears again or that you are reminded of again
Hearing that song again was a real blast from the past. macmillan dictionary
something or someone that surprises you because you had almost forgotten about it
something from the past that you remember, see, or hear again, and that reminds you of that time in your life
That’s a blast from the past. No one has called me that for years. Cambridge dictionary
Sometimes my brother goes to visit my parents and sends me a picture of an old something in my parent's house: One of my old toys, my old Advanced Dungeons & Dragons rulebooks, comics or the like. It's usually something that we haven't seen or even think about in literally years or decades, and it may have a strong emotional baggage (it's something we used to share, play together with, etc.).
When he sends me that kind of pictures via Whatsapp I'm included to just respond "a blast from the past!" and hope he'll get the meaning. A couple times I have tried
Viaje al pasado! / Regreso al pasado!
But that doesn't really convey the full meaning.
Is there in Spanish a better translation or expression to convey what
blast from the past means?