Itanagar, Sep 13 (PTI) The Indian Army in coordination with the Dibang Valley district administration in Arunachal Pradesh has began its second religious adventure trek to Athu-Popu, a sacred place for the Idu (Mishmi) tribe of the state.The expedition was flagged off on Monday.As many as 29 civilians including, seven female members of the Idu Mishmi community are participating in the trek along with personnel of the spear Corps of the Indian Army, official sources informed on Tuesday.The members of the expedition team will pay reverence at the sacred religious site.The trek would be completed in 17 days along a challenging and scenic route and would promote religious and adventure tourism in the area, the sources said.The first expedition to the site was organised on September 1, last year in which, Tine Mena, the state"s first woman Everester, participated.Athu-Popu has always been one of the most mysterious topics within the folktales and beliefs of Idu-Mishmi"s mythical world.Athu Popu is located approximately 290 km from Roing and holds a very significant place in local Idu Mishmi culture. It is located 3,500 metres above sea level at Kayala Pass in the Indo-China border with approximately 120 km from Maliney, the last village at a motorable distance of about 200 km from Roing, the headquarter of Lower Dibang Valley district. PTI UPL RG