extant
Still existing or surviving from the past.
Something extant still exists today, especially when talking about old documents, artifacts, or species that have survived from the past. When historians say the oldest extant copy of a book dates from 1455, they mean that's the earliest version still around: earlier ones may have existed once, but they've been lost or destroyed.
Scientists might study the extant species of an ancient family of animals: the ones still living today, as opposed to their extinct cousins known only from fossils. Libraries treasure extant manuscripts from famous authors, the actual handwritten pages that survived across centuries.
The word carries a quiet sense of survival against the odds. When you learn that only three extant copies of a rare book exist, you understand that countless others were lost to fire, floods, wars, or simple decay. Each extant artifact represents something that made it through when most others didn't.
Notice that extant is specific: it doesn't just mean “old” or “surviving.” A new book can be extant, but it isn't remarkable for being so. A thousand-year-old poem written on fragile paper that somehow survived is definitely extant: still here, still readable, still connecting us to the past.