Signalization and interlocking systems play a vital role to provide safe transportation in railway systems . Transportation on railways can be achieved confidently by the safety provided by these systems. Different methods including Petri Nets (PNs) can be used in designing such systems. In this study, interlocking and signalization design for a sample railway yard is achieved by Automation Petri Nets (APNs) which is an extended type of PNs. Once the model is obtained using APNs then it can easily be implemented into a programmable logic controller (PLC).