No, reservations for the ride up are not necessary, though highly recommended for groups of 20 or more. Simply contact us by email to firstname.lastname@example.org
The SchafbergBahn timetable is very flexible, so that the frequency can be increased during peak demand to intervals as little as 20 minutes apart. Needless to say, this keeps waiting times to an absolute minimum.
Nevertheless, if you want to guarantee a specific departure time, you should go ahead and book your ticket online in advance.