On the crater floor, many are several hundred feet high.

Its lower edge was at least three thousand feet above the crater floor.

Was there a vast engine deep under the crater floor?

He did not know where they were on the crater floor.

Most of the current crater floor was formed in 1974.

The crater floor is flat and it has a central peak.

I'd be exposed the whole time I was on the crater floor.

There is a low ridge on the crater floor running from the north wall.

The central peak forms a range on the crater floor.

For suddenly I knew what the dead man out on the crater floor had written.