Only the occasional fatal dispute broke out, which ACT ranger Adrian Brown suspects was probably over women. One clash became so ferocious it raged for days, from the Murrumbidgee River all the way to Mount Clear.

Differences have long been settled and at sunset on Monday, traditional custodians of the mouth of the Murray River will perform a ceremony with their counterparts in Canberra, the Ngunnawal people.

For the first time in 200 years, singing and dancing will reawaken an ancient pathway that connected their nations for more than 25,000 years.

Mr Brown, an ACT Parks and Conservation Ngunnawal ranger, said old men from the two countries would meet every few years to swap information on land management, decide who would marry who and who would progress to the next stage of land management.

Mr Brown read of a fight in the old days at Duntroon when Ngunnawal people drew a line in the sand with the Ngarrindjeri people.

''No one knows what they were fighting over. It could have been women or a resource. They often fought over women.

''Women could give you so much more opportunities in the tribe, because they are the collectors. They are also the first teachers for the young boys and girls. They are really important. They would often get stolen.''

Men from both countries watched each other for several days.

''Then their courage must have built up and they fought with spears and big shields. When the fight finished with the spears, they came in with the nulla nulla, the clubs, and harder shields.

''Three of the guys were wounded from Ngarrindjeri. One of them died near Booroomba Rocks near Tharwa and two more died out at Mount Clear (in Namadgi National Park).''

Murra Bidgee Mullangari, which means Keeping the Pathway to our Ancestors Alive, will be performed at Uriarra East picnic area.

Mr Brown said traditional dances always began at sunset, to dance up the spirits and talk to them through their songs.

''Every time you stamp your foot, that is singing the spirits. They hear that and know you are there and you are talking to them.''

Mr Brown said the Canberra community was invited to see this rare exchange of traditional dances on the banks of the Murrumbidgee River.

Ngarrindjeri Elder Major Sumner from Coorong in South Australia and the Tal-kin-jeri dancers will perform the ceremony with local Ngambri dancers.

Major Sumner said it was a privilege to be invited to join the Ngunnawal and Ngambri people in an important ceremony of culture and connection to the land.

''These friendships that existed for thousands and thousands of years were separated for 200 years, and now we are coming together again,'' he said.