In recent years the intensified development of investments in housing, industrial and infrastructure requires large amounts of rock materials. In the event of significant shortage of aggregates in some regions, there occurs the necessity to transport them from the regions of excessive production capacities comparing to their own needs. For transport of aggregates in Poland basically two types means of transport are used: trains and cars. The type of transport is usually chosen on the basis of technical possibilities and economics. Generally rail transport does not exist as such, because it is necessary to combine it with car transport to deliver the aggregates to railway siding and then to the recipient. This paper presents the results of a study on the cost of aggregates transport by road and rail. The viable distances for each kind of transport are specified for different load capacities and the needed discounts are evaluated. In conclusion, the need to make greater use of rail transport to deliver aggregates over long distances is emphasized, and the necessary modernization of railway network is pointed out.