In Leosia, a small settlement, in the middle of the forest, a huge boulder stands alone. It is the largest erratic boulder in Pomerania (and one of the largest in Poland), a remnant of the last ice age. 24.5 m in circumference, 8.8 m wide and 3.8 m high - these are the dimensions of this granite giant. Eratyk, which is a monument of inanimate nature, is called the Stone of St. Adalbert (Wojciech) or the Devil's Stone. Where do both names come from? As is the case with large boulders, each of them has a legend behind it... One of them says that on this stone St. Adalbert preached a sermon during the Christianization expedition to Prussia. The second one tells the story of the devil who, wanting to change the course of a river, planned to block it with a huge boulder. Surprised by the coming dawn, he abandoned the stone in the forest and it remains there to this day...