Mare Chronium

They went bouncing by across Xanthus just as they'd bounced by us back in the Mare Chronium.

So the two of us plugged along across the Mare Chronium.

It was just before twilight that I reached the edge of Thyle, and looked down over the gray Mare Chronium.

Mare Chronium was just the same sort of place as this—crazy leafless plants and a bunch of crawlers; I gave it a glance and hauled out my sleeping bag.

I decided to sleep on the plateau if possible; anything dangerous, I reasoned, would be more likely to prowl through the vegetation of the Mare Chronium than the sand of Xanthus.