About the organ
Wielisław Organ (Organy Wielisławskie) at the foot of the Wielisławka hill above the Kaczawa River is one of the most famous geological sites in the region, visited since the late 18th century and protected as a natural monument. In the excavation of the former quarry, rhyolites, silica-rich volcanic rocks from the Permian period, are exposed. They are regularly cracked, resembling a large inverted fan. There are two main directions of rock fractures, forming hundreds of adjacent hexagonal columns with a diameter of 20–30 cm. The arrangement of the columns changes in space. In the northern part of the quarry, they are set vertically, which is also visible in the rock walls to the north of the quarry. In the southern part, their inclination decreases until it becomes horizontal. Such variability indicates that the solidifying lava formed a dome-shaped structure.
History
Wielisław Organ mark the beginning of the trail to the summit of Wielisławka Mountain, where a nature trail leads. At the summit, there was a medieval hillfort, later a small castle, destroyed in the mid-15th century. The remnants of earth fortifications are the only traces left of it.
The slopes of Wielisławka were the site of mining activities from the mid-16th century to the 18th century, focusing on polymetallic ores found in hydrothermal veins. The remnants of these activities include sunken shafts, spoil heaps, and underground excavations. The longest adit – the Wielisławska Cave, measures approximately 100 metres in length. At the foot of the hill, there is an old mill recently renovated and now operating as an accommodation facility with a restaurant.
Description: Piotr Migoń
A walk to the summit – along the nature and gelogy trail “Wokół Wielisławki” (“Around Wielisławka Mt.”)
