It's called "domestic tourism", not internal tourism. Domestic tourism is when you travel inside your own country. International tourism is when you travel to different countries.

srgause is incorrect about internal tourism. Internal tourism is actually a recognized economic concept. Definition: Internal tourism is the tourism of visitors, both resident and non-resident, within the economic territory of the country of reference.

in my point of view , i think that internal tourism is when someone want to discover his own country, with its nature , monuments , cultures,,,,,, and then this person does not need to learn more forgnien languages to do that sort of toorism, in the opposite of that inernationl tourism , when people know a lot about thier cultures , and want to enjoy others cultures ,,, so they need to learn how to commnicate with them ,,,,,,

I stand corrected! At the risk of sounding like a dictionary while speaking, use internal tourism. :)