Karlu Karlu Conservation Reserve has received international recognition, becoming the Northern Territory's first and Australia's third International Dark Sky Sanctuary.

The 1800-hectare reserve, about 100 kilometres south of Tennant Creek, is well known for its large granite boulders, but it also holds deep cultural significance for Aboriginal people across the Barkly region.

Almost all of Karlu Karlu is a registered sacred site and is significant to Kaytetye, Warumungu, Warlpiri and Alyawarra Traditional Owners.

DarkSky International says Karlu Karlu is a cultural landscape central to the identity of Traditional Owners, whose ancestors have cared for the area since creation time.

The successful Dark Sky Sanctuary submission was led by the NT Department of Tourism and Hospitality, with support from Traditional Owners, the Central Land Council, Barkly Regional Council, Tourism Central Australia and the Devils Marbles Hotel.

DarkSky International Program Manager, Amber Harrison, said the recognition demonstrated how protection of the night sky could sit alongside the protection of culturally significant places.

"This award is an excellent example of how dark sky conservation can complement the protection of culturally and environmentally significant places," Ms Harrison said.

The designation places Karlu Karlu among a small number of International Dark Sky Sanctuaries around the world.

The status recognises locations with exceptionally dark night skies and protected environments, with Karlu Karlu joining Arkaroola Wilderness Sanctuary in South Australia and the Australian Age of Dinosaurs Museum of Natural History in Queensland as Australia's three recognised sanctuaries.

The application process took about a year and included six months of night-sky readings, an assessment of artificial lighting and consideration of future risks to the area's dark skies.

NT Parks and Wildlife Operations Senior Director, Philip Cowan, said the designation would also place conditions on future development.

"This designation will help protect the night sky at Karlu Karlu, ensuring any future development must adhere to strict lighting guidelines, ensuring preservation of the night sky for future generations," Mr Cowan said.

The Department of Tourism and Hospitality intends to develop formal night-sky viewing infrastructure and new signage, including interpretation of the night sky through Aboriginal-led storytelling.

Northern Territory Minister for Tourism and Hospitality, Marie-Clare Boothby, said the international recognition was also an important opportunity for the Barkly.

"This is an absolutely stellar achievement," she said.