[Sequitur]

For the European inland waterways, you need an additional endorsement to your International Certificate of Competency (ICC). So if you intend to go inland here, you need something to endorse.
You also need to pass a simple test to get the endorsement.
http://www.unece.org/trans/doc/finaldocs/sc3/ECE-TRANS-SC3-115r3e.pdf
All those regulations are not my cup of tea, but they are enforced :hothead

Yup, I sure remember the CEVNI when I had my canal boat in France. Had to sit the exams in French back then; they've probably changed that now that the Code is available in English.