Thanalan -> La Noscea

[SkyfangRauss]

technically vesper bay is locked until 30, however, if you haven't done the envoy quest the ferry ticketer will tell you that 'the ferry is closed until futher notice'

once you get the airship pas, the dialogue changes to 'you must be level XX to ride the ferry'

[Kraggy]

technically vesper bay is locked until 30'

Er, no, I rode the ferry at 20, I have no idea when it unlocked so it may have been 15 when I got the airship.