The Church Stretton Fault is a very important feature affecting the geology and therefore the landscape of not only Shropshire but all the way from Cheshire down to the southwest corner of Wales. It has been to some extent active throughout Phanerozoic time (i.e. since the evolution of creatures with hard parts: shells or skeletons, from about 650 million years ago). Its route through the Stretton Valley is fairly obvious, marked by the contrast in rock types between the east and west sides.
There are other faults in Shropshire, notably the Pontesford-Linley fault which runs along the western side of the Longmynd, causing the dramatic drop as one drives west from Church Stretton. These also play a part in the look of the landscape today.
Need to get hold of the geological society for an image.. and permission to link
A paper by nationally renowned geologist Dr Peter Toghill on the geology of Shropshire and Herefordshire.