On the peak of 902 meters above see level the archaeologists discovered the fortification from iron age - the Celtic oppidum (fort). The fort has a shape of polygon, is 403 meters long and 114 meters wide. The total  side-walls stretch in a length of over 920 meters. Numerous archaeological researches found out that the place was settled by the Celtic Boi tribe. The inhabitants of the fort were mainly gold-washers. They were panning gold along the whole river of Otava as well as the adjoined streams. In vicinity of Dlouhá Ves there are remainders of gold-washing (sejpy). The Celts allegedly called the mountains of Šumava Gabreta, which means Golden Lands. The Otava was for a change called Atava, which means Golden River.