Yes, most hotel room reservations are fully refundable if you cancel prior to the hotel's cancellation deadline, which often is within 24-48 hours of the scheduled arrival. If you have a reservation that's non-refundable, you may still be able to cancel and receive a refund within a 24-hour period of booking. Plug in your dates, click on "Search", then use the filter option "fully refundable" to review the best options available near Helikon-Opera.