I really like Thomas Swick's definition of travel:
Today I think of travel as anything that extends one's realm of experience or expands
one's lexicon of acquired convictions and occurs beyond the backyard (this
distinguishing it from reading).
From "Charmed Lives: Reflections of a Travel Editor on Abroad
The Oxford American
. March/April 2001, p. 58.
Swick relays in his article a story about "traveling" to a friend's house, where the style
of parenting was 180 degrees from anything he knew. In his mind, this was traveling
to a foreign place as much as going to Paris.