Problem: It's not really obvious to me where TrailRunner stores the main document containing routes and the database containing my diary activities. How can I backup these files?

Solution: TrailRunner stores files in the following folders. Backup these folders/files and your personal data is safe.
__yourhome__/Library/Application Support/TrailRunner
__yourhome__/Library/Preferences
__yourhome__/Library/Caches/com.berbie.trailrunner

> Read More about what files TrailRunner writes to your harddrive…

Hint: Another alternative to backing up your files is to place them in Dropbox. This also enables you to synchronize with other computers you own:
> Read More about how to synchronize your diary with other computers…

Hint: on Mac OS X Lion the __yourhome__/Library folder is invisible by default. But just hold down the option key while pulling down the Finder's "Go" menu to get there. Or you can make it permanently visible using the following terminal command:
chflags nohidden ~/Library/
or you can open it by typing the following into the Finder menu item Go > Go to Folder box:
~/Library

Tags: backup, diary, synchronize, dropbox, preferences