Adaptation of existing level crossing of road I/23 and II/602 near Ostrovačice in the South Moravian region is solved in the diploma thesis. The level crossing is a transversal crossroads with four-lane major road, directionally divided. It is place of frequent traffic accidents. The outputs of road traffic survey made for the purpose of the thesis, the evaluation of rate of accidents and the capacity analysis of 5 versions of process layouts of the crossroads with detailed commentary are contents of the thesis. The thesis also includes the section of the drawings resulting from the previous sections. The first layout is a low cost, different road marking and traffic signing are the only changes. The second layout is conversion to the spiral roundabout.