This paper presents the results of unconfined compressive strength tests carried out on samples of two different fine grained soils mixed with anthropogenic materials produced in Poland, showing binding properties – cement kiln dust and fly ash obtained from combustion of brown coal in a pulverized boiler. The tests were performed on cylindrical samples in a testing machine for compression tests after various curing time ranging from 1 to 8 weeks. The conducted work constitutes the first stage of research devoted to the recognition of the effects of calcareous fly ash and cement kiln dust addition into the fine grained soils.