Many events offer the possibility to purchase a cancellation insurance along with your tickets.
This insurance renders it possible to cancel your ordered tickets as a result of certain events, such as a serious illness, a serious accident, injury or death of the insured person or a close relative, pregnancy complications, serious damage to the vehicle used to reach the event, etc. For all the details please follow the link below.
Careful: this insurance does not cover cancellations that might result from terrorist threats.
You may look for more information here.