て form and number, what does it mean example: “ザーレスが滅んで千年”

Question

Sentence:

　それがサングルド山脈のどこかにあるというのだが、ザーレスが滅んで千年、いまだに入り口すら見つかっていないのだ。

Is it "...after destruction of ザーレス thousand years passed, and even now..."

Answer 1

It is precisely as you stated.

「Verb in て/で-form + time period」

means:

"(It has been) N weeks/months/years/centuries since (event described by the verb phrase)"

Informally, you can insert 「から」 between the て/で-form and the time period.