finding the path

The route between landmarks or events is constrained by both space and time.  Charting these paths means you have considered the virtues of mapping and relative position between locations without handwaving it.  The last only needs to occur when you hit a tipping point of setting complexity.  There's a reason that every fantasy trilogy you've ever read has a map - the author needed to know where stuff was - with the notable exception of Terry Pratchett. 

"There are no maps. You can't map a sense of humour."
                        -- Terry Pratchett, Discworld author.

Eventually though the Discworld succumbed to cartography. 
Typically, there are three kinds of path:

Obvious - Taken by about 80% of your setting population. Clearly marked, maybe with milestones to show progress or landmarks to give navigational reference.

• Predictability - If you take this path, you will get to your destination.
• Ease of Use - This option is the most accessible (otherwise, why use it?) to the majority.
  

Obscure - Paths your environment allow that are less obvious.  These may require some exploration or even trail blazing.  Not all hidden paths are advantageous - for example the proverbial shortcut that takes twice as long. There are two reasons to go the road less travelled. 

• Opportunities - to reduce inconvenience (avoiding a toll) or reveals benefit (an untended apple tree).  This is one of the main reasons for adventure.
  
• Options - Where the obvious path is obstructed, you have an additional option. 

Least resistance - Favoured by liquids, winged things and the lazy.  Note the path of least resistance is not always rewarding or without hazard.

• Speed - Sometimes you're in a hurry.  You may not want to meet the travelling gypsies, find treasure or kill a dragon.  You might just want to go home.
  
• Safety - When you absolutely, positively have to get there.  Self-preservation is a concern raised in a number of blogs where heroism is tinged with pragmatism.
  

Designing with these paths (and their objectives) in mind enables you to anticipate particular strategies and can help build causality into your setting.  Including limited, minor choices on a particular path preserves a sense of choice without resorting to illusionism (a phenomenon in some games where no matter what you do you end up somewhere usually undesirable or divorced from causality) or railroading.