how can I raise the level of my captain to go to the expedition in the Mediterranean?
Patrician IV rise of dynasty

the easist is to pay the trainers to up the navagation skills of your captains using the trainers in certina citys taverns. forgot were the Nav trainer is.

OR you can make up you convoy and set up an auto route going to 4 or 5 citys and seting them to just auto trade every type of cargo at those citys. a few months game time and he should have a 3 navagation + it will up your rep in those citys and generate cash too. it also ups your captains trading skills which is useful in the med citys.

Battle trainer = Reval
Navigation trainer = Edinburgh
Repair trainer = Oslo
Trade trainer = Lubeck

Try to do training as early in the game as possible. The higher your rank and wealth, the more expensive training becomes. (By the time you are worth @ 2 million and your rank is above Traveling Merchant, starting at skill level 1 of anything will cost >1 million by the time he gets to level 5. In contrast, if you do all five levels of training in the first couple of months, the total cost can be <15,000.)

your captain only needs nav skill at 3 to be able to go to med.
all ships in the convoy must be at least cogs with health >90%.

Lebe jeden Tag, als wäre es Dein Letzter! / Live each day as it would be your last!