The Hackness Hills image above was produced via a Hillshade on Ordnance Survey OS Terrain 5 Data downloaded from Digimap (OS Terrain 5 [ASC geospatial data], Scale 1:10000, Tiles: se99ne,se99nw,se99se,se99sw, Updated: 2 April 2017, Ordnance Survey (GB), Using: EDINA Digimap Ordnance Survey Service, <http://digimap.edina.ac.uk>, Downloaded: 2017-07-13 09:40:15.365).
It is, of course, the wonderful groundwater-sapping formed valleys of the Hackness Hills in North Yorkshire. Below is a view from Google Maps –
These valleys are unusual as they are formed by the emergence of groundwater to the surface, so erode in a headward direction. This results in them appearing much stubbier and wider, and much larger than the size of the river would suggest. They are quite similar in appearance to some channels on Mars, and are seen as a terrestrial analog for the Martian valleys.
The nearby Hole of Horcum, just to the west, is thought to be formed by the same processes, but looks quite different.
The view from the top of the Hole of Horum (left) and inside the Whisperdales, Hackness Hills (right), taken by @floodskinner