According to this page on the Wikitravel site:
There are currently no database dumps of Wikitravel available for
download. Some people have asked to make dumps available.
However, the article does go on to state:
Reasons to make dumps available
Reasons not to make dumps available
So it looks like it is a work in progress at the moment. You could always sign up to help with the process of creating the data dumps.
Alternatively, you could use their API which is mentioned on this page.
API
A MediaWiki API for programmatic access to the site is available at
http://wikitravel.org/wiki/code/api.php, where code is one of the
language versions of Wikitravel, eg. "en" for English. When using the
API, please follow the terms of use and download no more than one
article every 30 seconds, or you may be blocked without warning.