Outback

The Outback is the vast, remote, arid area of Australia. The term "the outback" is generally used to refer to locations that are comparatively more remote than those areas named "the bush" which, colloquially, can refer to any lands outside the main urban areas.

Marvel Universe
One of the last major Sentinel factories, known as the Ant Hill, was located in the Australian Outback. The Sentinels engaged in an ambitious plot to sterilize Earth's mutant population by creating a solar flare from this facility. They fought up against the Avengers and were defeated. Iron Man buried the facility beneath a pile of rocks.

For a time, the world believed that the X-Men were dead. Having gone into hiding, the X-Men headquartered themselves in the Australian Outback for a while. This was also the base of operations for a band of cyborgs known as the Reavers, who were led by Donald Pierce. It was during this time that the X-Men first encountered Jubilee.

Jubilee and Wolverine later fought up against Sentinel 3.14159 here. The Sentinel revived the Sentinels at the Ant Hill in an effort to duplicate a solar flare, this time to scour the planet of all humans.