Much of Laos lacks adequate infrastructure. Laos' railways include a short link to connect Vientiane with Thailand over the Thai–Lao Friendship Bridge, and a short portage railway, the Don Det–Don Khon narrow-gauge railway built by the French in Don Det and Don Khon in Champasak Province. It has been closed since the 1940s. In the late 1920s, work began on the Thakhek–Tan Ap railway that would have run between Thakhek, Khammouane Province and Tân Ấp station in Vietnam through the Mụ Giạ Pass. The scheme was aborted in the 1930s. Announced in 2015, a 414 kilometer high-speed rail line linking Kunming, in the southern Chinese province of Yunnan, with the Laotian capital of Vientiane is about 90% completed as of November 2020; the track is being laid, and the line is expected to be operational sometime in 2022.