The cost of the Nepalese section of the railway has been estimated to be from US$ 2.7 billion up to 5.5 billion, but no agreement has been reached yet over the funding, with Nepal unable to bear the full cost of the railway. A Chinese pre-feasibility study proposed a tunnel under the Langtang National Park to avoid a steep gradient and building in the protected area. In a straight line, the distance between Kathmandu and the border with China is just 70 km.
