The road we were on had yet to lead past any sign of civilization.

There are some signs of civilization even deep within the park.

You'd have to be less than a thousand miles up to see signs of civilization.

So far no signs of civilization were to be seen.

In a little while they had left behind them all signs of civilization.

No sign of civilization or assistance caught the Doctor's attention.

"It's just been so long since we've seen any sign of civilization."

Moreover, here was no sign of civilization, even from a hundred miles up.

Three more days and he reached the first signs of civilization.

Here they saw the first signs of civilization beyond that which they'd left behind.