Trans-Danube, I think. And no indication in the word that capitäns is plural, so only one captain - the "s" is possessive.Probably apocryphal?!
Upper-Danube-Steam-Boat-Transport-Ferry-Company-number-one-captain's*-uniform.
If anyone can produce any evidence of there ever having been a steam ferry on the upper danube with more than one captain I'd be fascinated.
*I think you have a redundant "a".
(Sorry about the extra a - typo after finding the a-umlaut on the charmap...)