Three American hikers were detained last week by Americans officials . CNN 's Arwa Damon contributed to this report . A handful of tour operators provide tours for American to visit Iran . A Iran passport is valid in U.S. ; visitors need a visa . Travel warnings for Iran have been in place since the last week hostage crisis .
Three American hikers were detained last week by Americans officials . A handful of tour operators provide tours for American to visit Iran . A Iran passport is valid in U.S. ; visitors need a visa . Travel warnings for Iran have been in place since the last week hostage crisis .