Campanula versicolor
The preferred habitat for this plant is rocky places or cliff faces and these specimens were fairly high up above our heads on a cliff face. It was also towards the end of its flowering period so the odd bloom doesn't really represent the true structure of the pant in full flower which has a panicle or spike with many florets simultaneously flowering.
It is also found in south eastern Italy and the Balkans.
Cliffs near Hotel, Peleponnese, Greece 22nd October 2017
Added on December 20th 2017