Burgberg

The Oestricher Burgberg rises above the Lenne river near Oestrich, a district of Iserlohn in the Arnsberg region. Its slopes show the striking rock formation called Pater und Nonne and the Grürmannshöhle cave. The hill is made of limestone that has been quarried in open-cast workings for decades. On the summit stood the medieval Oestricher Burg, whose earthworks still mark the skyline. In 1928 labourers found two gold ornaments from the 4th century at the foot of the hill. The hill and its surroundings became a 41.5-hectare nature reserve in 1997, protecting two separate areas on either side of the B236. Botanists have recorded the bee orchid on the limestone grasslands beside the eastern quarry. The same slopes shelter the Zwerg-Bläuling, a butterfly so rare in the north-west Sauerland that it appears only here. After 24 years without sightings, the protected Purpurwidderchen moth was recorded again in 1992. Visitors walk the marked paths that circle the old ramparts and lead past the Pater und Nonne pinnacles. The Grürmannshöhle cave lies within the reserve’s eastern section, its entrance framed by scrub and limestone debris. From the summit the view stretches over the Lenne valley and the surrounding limestone plateau. The contrast between the ancient hillfort and the working quarries below shows how natural and industrial landscapes can share the same ground.