During the international tunnelling and underground space seminar in Beijing, China, on 25 March 2019, ITACUS tutor Prof. Chungsik Yoo outlined his vision on underground space in a powerful opening speech. "Due to the limited surface space available, tunnelling has become an attractive alternative in creating spaces for the transportation networks. An ever-increasing awareness of the environment has also given favour to tunnelling over other construction alternatives. In response to such an increasing demand for tunnels and underground spaces, a significant length of tunnels for subway lines in major cities, high-speed railway, and highway road has already been constructed and is operated. More tunnels and large underground spaces for a variety of use are scheduled for construction in the years to come", he started his speech. Download the full text of his speech below.