What do you call those man-made "wooden paths" that are usually found in mountains?

This what I'm referring to:

I guess the starting section can be called wooden steps, but as it goes further, it's no longer a step but a "path." What do you call the whole structure? (I'm looking for a common-easy-to-understand term, rather than a technical one).

The U.S. National Park Service uses them extensively In Everglades National Park. (obviously without the steps.) They are described as boardwalks in both the Park Service literature and by those of us who use the Park. I realize the word is also used to describe a similar structure along a beach, but "context is everything."

I would call that a [wooden] walkway.

I have most often encountered them in national parks or other scenic areas where they have been used to allow walkers to cross over swampland without getting their feet wet or damaging the ground and plants.

Another possibility is decking.

I think you already found the most common and easy-to-understand term. It is a wooden path. (you can also call it a "wooden pathway").

The whole structure can be called a path or a pathway also. A path can be elevated and it can have stairs, steps and rails.

The wooden path in your picture can be called a wooden trail or a wooden plank trail also. The photo is from Alishan National Scenic Area in Taiwan. Its official website calls it a wooden plank trail too.

A close up of the new wooden path leading up from Dersingham Bog

More examples:

Note: Also mentioned as "tree top way" or "tree top walk".

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