A large petrified tree that lived around 330 million years ago has been ... this case iron and calcium carbonates - while the plant retains its original shape and structure. This fossilisation process ...

If you are looking for a unique state park, head to central Washington for a forest of petrified trees of a species so old they are called "living fossils." ...

Pit houses are structures whose floors are dug down ... this loop will lead you past some of the largest petrified trees in ...