The Zillertalbahn is more than an arrival detail. The narrow-gauge railway makes Mayrhofen one of the easier Austrian resort towns to use without a car, running down the valley to Jenbach and the mainline rail network.
In practical terms, it lets you treat the Zillertal as a connected valley rather than a series of isolated villages. In summer, special heritage-style services sometimes add a little railway romance to an otherwise useful transport line.