You need insurance, and this is compulsory if you’re undertaking any adventure activities. This can become very important if a member of your party falls ill and needs helicoptering out of the mountains. Most insurance policies have very strict conditions on what activities you can and (mostly) can’t do. We can safely recommend Nomads for worldwide residents and Trailfinders, but only for residents in Europe. Please check the details on Adventure Activities at Nomads and Trailfinders cover at either site and e-mail them if necessary.