This chapter presents a case study of the “Buna” bridge in Croatia, which focuses on the design and implementation of new innovative solutions for transition zones between the open track on the embankment and the bridge. Starting with reviewing and evaluating the existing conditions by the application of geotechnical and geophysical investigation works, different approaches for both ends were applied for a systematic comparison of the overall performance. Innovative materials such as cementitious composites, geotextiles and geogrids were included in the design. Geotechnical-specialized finite element method (FEM) modeling work with PLAXIS software was then carried out for a preliminary analysis and evaluation of both approaches. Transitions were designed in a way that both settlements and stiffness variations are smoothened in a reasonable way so that both the safety and comfort of passing trains are not negatively affected at these locations.