The archaeological background of Lower Dibang Valley district is traceable from the pre-historic period. Exploratory works of the Europeans and their Indian counterparts in this region made it possible to understand the long history of the district. Among the prominent explorers Captain Gregory found a Neolithic implement called rounded Butt Axe from the Mishmi Hills.
Dr. Y.A. Raikar of the Research department, Govt. of Arunachal Pradesh collected three triangular Ground Axes and one Bar type polished broken celt during the excavation works at Bhismaknagar in 1970-71.
The Rukmini Nati (Ruins of Rukmini) named by Dr. Y A Raikar, officer-in-charge of the excavation, is situated at the heart of Chimiri village which is approximately 12 km from Roing. This is an hill-fort presumably of 14th/15th century. You find the remains of burnt and baked bricks, which indicates the progress of the erstwhile civilization. The legend, associated with the site tells that “Rukmininati” was the Palace of Princess Rukmini, the daughter of King Bhismak.
Excavation conducted at the site in 1972-73 reveals structure of two rooms measuring 10m x 10m x 12m, made of bricks up-to plinth level. About 19 kms from Roing at Injonu village a stone image of Ganesha was unearthed. It was made of granite rock, measuring 44 inches high and 27.5 inches wide. It clearly represents a pot bellied Ganesha in a seating posture. Of the four arms, the lower right is broken from wrist and other three arms are depicted with weapons like hand axe, conch etc. The mahout of Ganesha, the rat is also depicted at the bottom right of the image. There is a spiral line of decoration all along the boarder of the stelae. From the stylistic aspect, its antiquity could be placed in the 9th/10th century A.D.
Courtesy: http://roing.nic.in/archaeology.htm
PS: I had shown this web reference to him while he was around. His response was inimitable: a poker-faced look signifying "So What?"