Gardens & Palaces of Potsdam Bike Tour: We’re happy to offer free changes and 100% refund up to 24 hours before tour departure. Failure to cancel a reservation at least 24 hours prior to scheduled departure may result in forfeited travel funds. Fare difference may apply. Private Gardens & Palaces of Potsdam Bike Tour: Private Tours must be cancelled or rebooked at least 7 days in advance of the activity start time. Failure to cancel a reservation at least 7 days prior to scheduled departure may result in forfeited travel funds. Reschedulings are subject to availability.