Doing some reading about the historical guild system:

Like journey, the distance that could be travelled in a day, the title ‘journeyman’ derives from the French words for ‘day’ (jour and journée) from which came the middle English word journei. Journeymen were generally paid by the day and were thus day laborers. After being employed by a master for several years, and after producing a qualifying piece of work, the apprentice was granted the rank of journeyman and was given documents (letters or certificates from his master and/or the guild itself) which certified him as a journeyman and entitled him to travel to other towns and countries to learn the art from other masters. These journeys could span large parts of Europe and were an unofficial way of communicating new methods and techniques.