The Diploma Thesis gives a brief description of the railway lines in Slovenia and focuses on the issue at the line from Divača to Koper, where the advantages of building a second railway track are discussed. The theoretical part presents the theory of geodetic measurements simulation and introduces the data adjustment with all associated calculations. In the practical part we analysed the existing geodetic network of Glinščica and tried to upgrade it. The results are presented in a tabular and graphical format