The quarries in Nasiłów are considered an excellent geological open-pit and a model exposure of layers dating from the bordering Cretaceous and Tertiary Periods. The quarries offer an insight into the truly long history of the Earth: from before 70 million years ago. During that time, the territory of Poland was covered by the sea. It was warm, saline and about 1,000 m deep, which fostered the development of plant and animal organisms, such as corals, sea urchins, and brachiopods, as well as sharks, rays and large reptiles – mosasaurus. Gradually, as the result of the tectonic plate movement, the sea became shallow. The hexactinellid sponges living in the sea, which became limed with the shells of the foraminifera, constituted the main building component of the rocks exposed in the quarries, that is spongolites. The no longer functioning quarries used to serve in the past as the source of building stone. The rocks used for the regulation of the Vistula River were extracted from them. The Kazimierz spongelite, excavated in the local quarries, was also the basic building component of the oldest existing historical monuments in Kazimierz, the tower and the castle, as well as the mansions, churches and the pretty modern villas. A fantastic view opens up from the top of the quarry in Nasiłów on Bochotnica, Kazimierz Dolny, and the Vistula River picturesquely meandering here.