While reading some stuff on the South of France site, I found this magnificent rock formations that occupy region between the Marseille and Cassis in France called Calanques. They are 20 km long and maybe 4 km wide and are one of the great tourist attractions in Mediterranean France. Actually Calanque is deep valley with high rocky sides. Something like fjords and they are probably trails of ancient rivers.
Calanques in France are very special; they offer a magnificent views and panoramas. Also they are popular among the rock climbers who used them for trainings… Calanques are also home for Cosquer Cave. Most of Calanques are closed for public over the summer since high risk of forest fire exists. Because of that rule best time to visit them is from March to May. Calanques have specific ecosystem, almost without soil and water. Tourist usually takes boat trips or hiking trip through the premarked trails. Here are the breathtaking pictures (taken from escalade-calanques.com, wikipedia and pierrepisano.fr).