The project deals with the superior planning of the state highway network in Denmark. Within this context the work aims towards a development of the state highway route 15 passing through Silkeborg. The increase in traffic volumes has created a new situation for transportation planning, in which congestion problems will make up the main issue to be addressed in the decision-making process. There will in the future be a still larger demand for the limited resources available for new infrastructural projects on the superior road network. This is leading toward a need to incorporate useful alternatives to expensive new road links and extensions. Tools for planning, that can analyze and make prioritizations between all conceivable measures in an unbiased way, are not implemented in the planning process today. This project will introduce The Cube model as a possible new tool to address this problem. The model is used in a case study for the development of route 15 passing through Silkeborg. This road must be able to handle the flows in traffic satisfactory, before a new link is constructed to take over the long distance and commuting traffic. According to The Cube model, investigations are carried out for the mobility needs in the corridor of route 15 in a regional and local perspective. For the road, an analysis of conditions and deficiencies are also made for a present and future situation. Based on this, a strategy for all conceivable measures to improve the traffic flow is made. In this project, the focus will be kept on minor physical measures to improve the capacity of the road network. The effect of these measures is evaluated with real-time traffic simulation using VISSIM as a powerful tool. With presumptions in the growth of traffic, two scenarios are described in 2015 and 2025 respectively. In 2015 the traffic is handled satisfactory by optimizing and prioritizing the capacity in intersections with minor lane extensions combined with a 4-lane widening through one major intersection and along a central section in Silkeborg. In 2025 the entire bypass needs a 4-lane widening to handle the traffic. It is concluded, that The Cube is a strong though comprehensive tool to solve the complicated problems in Silkeborg. In a larger perspective, the model can be effective in the planning process for the state highway network, but the use of its applications is also determined by the present political agenda, and the will to make decisions based on a total view.