The course is designed to introduce to students the basic principles of geotechnical design and construction of railway and metro tunnels. Some technical issues relating to type and method of construction and design of tunnels in different ground conditions are presented. Helpful tools to assess the loads on tunnels and tunnel construction techniques fitting the local geological conditions are given. The main emphasis is to show the students the excitement associated with tunneling and the fact that many unknowns exist which require many years of experience and engineering judgment.