A fine population of Hart's tongue fern in Steinwandklamm, Lower Austria.
It is a narrow gorge, cut deep into limestone by a rather small torrent, giving perfect conditions for some various fern.
The site is the same where Hermann took the photo which is selected for iNat as representative for European type of this fern, Asplenium scolopendrium var.(ssp.) scolopendrium.

https://www.flickr.com/photos/hermannherbarium/4560865115/