OP I can vouch for what >>2818711 said. The Calanques is a really cool place, the water's beautiful, weather is nice year round and the scenery is really comfy. You could also try hiking up Mt Sainte-Victoire which is relatively nearby.

The whole of the south of France (minus the hemorrhoid called Marseille, but you have no reason to be there) is really beautiful with lots of awesome /out/ opportunities.