How do I say “full of obstacles” with one word?

Question

...paving the [full of obstacles] way to fluency.

Is there a one-word adjective I can use to replace that outrageous 3-word one?

I swear I've heard of it somewhere, but I've been searching for it for almost an hour now, and have come no closer to success than when I began.

Answer 1

Given that the phrase the desired word is going to be inserted into is a metaphor about paving a road, perhaps "rocky" will serve. This sense of the word is defined by oxforddictionaries.com as

Difficult and full of problems

Answer 2

If you're wedded to "paving", @DougWarrn's suggestion of "rocky way" would work. If not, you might want to consider:

"navigating the obstacles to fluency"

OR

"clearing the hurdles to fluency"

OR

"overcoming the pitfalls to fluency"

There are many possible word choices.

From M-W:

hurdle: something that makes an achievement difficult

pitfall: a danger or problem that is hidden or not obvious at first

Answer 3

It sounds like you might be looking for the word 'hindered'. According to dictionary.com when it can mean (when used without an object):

to be an obstacle or impediment.

To use it in your sentence I would more likely use the opposite:

...paving the unhindered way to fluency.

which implies that the path paved will be free of obstacles and impediments.

Answer 4

Perhaps, thorny works here. A thorny way is a way full of difficulties (synonym of obstacles).

...paving the thorny way to fluency.

M-W:

thorny adjective
2 : full of difficulties or controversial points : ticklish

stay out of the thorny brambles unless you want a ton of scratches

Usage examples: Google search for "thorny way"