We wanted to see the West Mediterranean Coast; Barcelona, Marseilles, Monaco, St Tropez, Florence and Rome, so decided to do this cruise with Viking. We thought late Feb - early March would be OK to travel, with some cool nights but weather in the 40's.
Barcelona was a wonderful place to embark - we spent a few days prior to the cruise - Gaudi, La Sagrada de Familia, the Castle, and some fabulous restaurants. We'd go back! Be sure to check out Cerveceria Catalan restaurant - it's a tapas place that is fabulous!
The weather was not great - we had cold and rain in Marseilles, couldn't land in St Tropez due to the wind, and even snow in Monaco - so be careful if you are thinking about the late Feb departure. You might get temps way lower than normal! It snowed in Monaco, so our French guide apologized for taking pictures. She had never seen snow in Monaco before - and she was in her 40's!