First joint archeological expedition

As part of the first cooperation agreement, the first attempt at cooperation after the short but bloody Yautja war, the first joint archaeological expedition explores the Forerunner city

Professor Belov: — Astonishing. The city is at least two million years old.

Tha'rak, Yautja, Archaeologist: — Not the city.

Belov: — What?

Tha'rak: — Specifically these walls. They're not the oldest here. And by the way, it says here that this is a hazardous materials warehouse. Best not to go in there.

Belov: — And the city?

The xenomorph runs a claw across the giant monolith.

Pause.

Kh'raash Kolyvan-Gyrkh-Tara, Sapper: — No one knows. Longer than we can remember.