forest path in the siebengebirge area near klosterruine heisterbach

europe germany park forest path siebengebirge area klosterruine heisterbach map stand nature signs guiding hikers scenic greenery cologne cologne landmarks europe fern foliage footpath path scenery walk fungus german forests germany grass green green landscape trees hiking hiking destination route heisterbach lage leisure natural beauty guide reserve signs trail outdoor adventure outdoors park perspective recreation rural scenic season shadow forest spring sunlight sunny trail map walking woodland