Warrumbungle National Park is located in central northern New South Wales, 550 km northwest of Sydney. The area is easiest accessed from the Newell Highway.
Outside of the Sydney metropolitan area parks, it is the most-visited national park in New South Wales.
It incorporates the most spectactular part of the Warrumbungle mountains, a region of past volcanic activity with unusual lava formations. There are many scenic bushwalks in the mountains. The park preserves habitat for a koala population numbering in the hundreds. It is also home to the Anglo-Australian Observatory, which has one of the largest optical telescopes in the southern hemisphere.
The nearest towns to the park are Baradine, Coonabarabran, Coonamble, Gilgandra, Gulargambone, and Tooraweenah.

The Park covers an area of 21,004 hectares.

The Breadknife is a dyke located in New South Wales, Australia. The dyke is nearly 100 m high, but often is only 2 m wide, which is particularly rare. The Breadknife was part of a large shield volcano, that first erupted about 18 million years ago and stopped about 15 million years ago. This shield volcano rose about 1000 m and is now largely eroded, forming the Warrumbungles.