Initially, it was proposed that the three areas would be connected by four major highways: Murree Highway, Islamabad Highway, Soan Highway, and Capital Highway. However, to date only two highways have been constructed: Kashmir Highway (the former Murree Highway) and Islamabad Highway. Plans of constructing Margalla Avenue are also underway. Islamabad is the hub all the governmental activities while Rawalpindi is the centre of all industrial, commercial, and military activities. The two cities are considered sister cities and are highly interdependent.