This is Bristol Rock Cress which only in the UK grows only in the Avon Gorge. We were hoping to see it in 'the gully' but ended up finding it right at the bottom on ledges alongside the A4.
It has creamy-white flowers...
And a basal rosette of dark green leaves which are unusually both shiny and hairy.
Bristol Rock Cress - Arabis scabra
This is Hutchinsia which we had more trouble finding than the Bristol Rock Cress. As you can see from the photo we had to climb up fairly high on the southern side of the gorge, fortunately only up a steep slab of rock. The blue in the photo is graffiti.
Hutchinsia - Hornungia petraea
Rue-leaved Saxifrage - Saxifraga tridactylites
Toothwort - Lathraea squamaria
This minute plant is Perfoliate, or 'Cotswold' penny-cress it was really difficult to spot being only around 3cm tall. It is rare and as the name suggests grows mainly in The Cotswolds. It's called perfoliate as the leaves appear to completely surround the stems as if perforated by them.
Cotswold Penny-cress - Thlaspi perfoliatum
Pasqueflower - Pulsatilla vulgaris