In this paper, emphasis is placed on the R106 regional line, given its relevance to the daily mobility of residents from the Zagorje region to the Croatian capital, Zagreb. The R106 railway, on the one hand, enables traffic to the railways of the neighbouring Republic of Slovenia, and on the other it is connection to the regional railway R201 Zaprešić - Varaždin and the international corridor M101 as a connection with Zagreb. Part of the R201 line is stock Zaprešić – Zabok, the section to which the R106 line connects and is currently being overhauled, electrified and equipped with modern signalling devices. Upon completion, it will be possible to utilize 50% more capacity of that section of the railway, but also to include it in the Zagreb sub-urban ring. This will increase mobility throughout the entire Zagorje region. Consequently, to meet the generated increase in demand, it will be necessary to increase the number of trains on line R106, but also to increase its existing capacity, as it will gain even more importance, both for regional traffic and for daily local migration of the population to go to business, administrative and other needs. In view of this, the paper describes mentioned specific circumstances, which give rise to the need for more detailed research and looks at the existing technical characteristics of the R106 line. Accordingly, additional measures are provided for rail and station security, whose impact on capacity will be determined through simulation using the Opentrack software package. The implementation of the proposed measures would contribute to increase the capacity of the R106 line, but also to increase its importance not only at regional level but also in the context of border and international traffic.