There are two basic itineraries in ther Mediterranean. The Eastern Mediterranean itinerary almost always starts or terminate in Istanbul, Turkey and the Western almost always starts or terminates in Barcelona, Spain.
 

Eastern Mediterranean
Major Cruise Lines

Celebrity Cruises
   [ Millennium ]

Costa Cruise Lines 
   [ CostaAtlantica ]  [ CostaVictoria ]

Holland America Line
[ Noordam ]  [ Oosterdam ]

Princess Cruises
    { Golden Princess ]  [ Royal Princess ]

Royal Caribbean International
    Grandeur of the Seas

Other Cruise Lines

First European Cruises
    Mistral  
Orient Lines
    Crown Odyssey  
    Marco Polo  
Royal Olympic
    Olympic Countess  
    Olympic Voyager  
    Stella Oceanis   
    Stella Solaris  
    Triton  
Silversea Cruises
    Silver Wind

Renaissance Cruises
    R-1
    R-7  

Western Mediterranean
Major Cruise Lines

Celebrity Cruises
   [ Constellation [  [Millennium ]

Costa Cruise Lines
    [ CostaAllegra ]  [ CostaClassica ] 

Holland America Line
[ Noordam ]

Princess Cruises
    { Golden Princess ]  [ Royal Princess ]

Royal Caribbean International
[ Legend of the Seas ]

Renaissance Cruises
    R-1
    R-2 
    R-5 
    R-6  
Royal Caribbean International
    Legend of the Seas  

Other Cruise Lines

Orient Lines
    Marco Polo  
Star Clippers
    Royal Clipper  

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