China has proposed the Nepal government to build a rail tunnel beneath Mount Everest. According to various reports, the neighbouring nation is extending a railway line linking the capital of Tibet to Nepal via a tunnel under the tallest mountain in the world.

Engineering projects on an extreme scale are nothing new for China. The proposal is the latest in a series of ambitious rail schemes Beijing is reportedly examining. The country already has built the longest bridge in the world—the Danyang–Kunshan Grand Bridge—and the third-longest tunnel, the Dahuofang Water Tunnel (the longest is in the US). However, it comes amid scepticism about whether some of the projects will ever get off the ground and at a time of a growing Chinese presence in Nepal, which has caused some concern in rival regional power India.

The Qinghai-Tibet railway already links the rest of China with the Tibetan capital, Lhasa, and beyond, and an extension running as far as the international border is already being planned. The project is expected to be completed by 2020 as cited by a Chinese newspaper.