Other ant-free areas in the world include parts of Polynesia and a few remote islands in the Atlantic and Indian oceans. Aside from that, ants are pretty much everywhere.
Ants make up at least 15 percent of the terrestrial animal biomass. That is to say, if you weighed all animal life on land in the world, 15% of it would just be ants!
This is a picture from the 1954 movie Them! It's kind of cheesy and the special effects haven't aged well, but I recommend it.