Why didn't Stu, Larry and the two other men just go around that big canyon in Utah instead of climbing down into it?

Also the inaccessibility of the major canyons in the Himalaya contributes to their not being regarded as candidates for the biggest canyon.

Now the big empty canyons funnelled nothing but wind.

Together they came to the big canyon called Nilokeras Scopulus, and dropped into it on a broad rough natural ramp.

An ironic name for the biggest canyon in the solar system.

The big canyon ought to be no more than a few kilometers away at most, and very probably it had water at its bottom.

Now something was wrong with the walls and mesas and promontories of the big canyon too.

There's a constant thermal over that big canyon"' "May I ask what you're reading on the planer's surface?

A foottrail that led down the wall of the big canyon invited him, and he proceeded to follow it.

We've got to find out if the bigger canyons are like that!