What is Another way of saying seen before?

Here are some ways to say "seen before", depending on the context:

Formal:

* Familiar

* Previously encountered

* Priorly observed

* Recognizable

* Known

* Experienced

* Witnessed

Informal:

* Been there, done that

* Old hat

* Déjà vu

* Seen it all

* Heard it all before

* Been around the block

* Nothing new

Specific to different contexts:

* For a person: "I know that guy, I've met him before."

* For a place: "I've visited this museum before."

* For an event: "I've attended this concert before."

* For a situation: "I've been in this situation before."

Choose the best option based on the level of formality and the specific context of your sentence.