naure.com
NatureSurprise 5/5Difficulty 4/5Reviewed on September 13, 2026

The Petrified Forest in Arizona has tree trunks more than 200 million years old.

Why it is true

The Petrified Forest in Arizona contains tree trunks that lived more than 200 million years ago, in the Triassic period. The wood was replaced by minerals such as silica, turning into stone. It is one of the largest deposits of petrified wood in the world.

Source: National Park Service

Would you rather be asked first?

This is the reading side of the site, so the answer is in the sentence above — that is the whole point of it. Test yourself works the other way round: the question comes on its own, and the fact and the explanation only appear once you have answered.

Test yourself →10-question challenge

Related facts

More in Nature

See all →