Kekar Monying (Black Rock) is a beautiful mountain cliff located close to Rottung, in East Siang District of Arunachal Pradesh. It was the historic site where the Adi put up a strong resistance against the British in 1911. The war was a part of a punitive expedition undertaken by the British for murdering Noel Williamson, a political officer in the previous year by Matmur Jamoh, a native of Yagrung village.

Komsing, situated on the banks of Siang River, is the site where Williamson was murdered. There is a stone epitaph bearing the name of Williamson.

Recent excavation conducted by the Archaeology of the Research Department reveals the glorious past culture of early medieval period (probably Pre-Ahom). There is a big rectangular canal and a pond in the spot. A mound has been unearthed inside the Canal area; most noteworthy fact is that 13 different sizes of bricks have been found from its brick wall.