construction of the China-Laos Railway has very numerous tunnels.
Engish news Xinhuanet.
http://www.xinhuanet.com/english/2020-08/23/c_139310648.htm
http://www.xinhuanet.com/english/2020-08/23/c_139310648.htm
Feature: Chinese builders work hard to press forward Lao projects to forge LMC Economic Development Belt - Xinhua | English.news.cn
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