This well-illustrated final report for the Swiss Federal Office of Energy (SFOE) reports on the development of a vertical drilling apparatus named Terra-Drill. The various stages of the development of the apparatus, which is based on earlier designs, is discussed. New norms issued in Germany for the size of boreholes for buried vertical heat-exchangers and the appropriate linings to be used are discussed. The new Terra Drill 4407 V drilling apparatus and its testing are discussed. The drill is quoted as being particularly suitable for cramped locations. Technical details are presented and a comprehensive collection of photographs is included. Various preliminary reports and development documentation are included.