Nationzoom.com is not selective in terms of creating inbound traffic as its promoters apply redirect technologies both online and off-line.
The latter may be casual and due to visiting websites that contain unverified ad links. The former are critical and require Nationzoom.com removal via relevant trojan extermination; this being said, there is a piece of adware that runs the redirect so that any url you type into your browser address bar may be intercepted and the unwanted page would load instead (it as well loads as a start page, new tab default etc.).
The adware is typically loaded as a part of freeware; to be precise, it is added to a content grabbed from the Internet without duly notifying people who perform loads, unless a graying out ticked box or a provision at the middle of some lengthy agreement is to be considered a proper way of making people aware of what they are about to install.
Let free scanner inspect your PC so that would be able to remove Nationzoom.com and any other threats as reported by the detecting solution.