Travel insurance is the important for indoor and outdoor traveler. Travel insurance must be cover medical and emergency evacuation cost. The insurance should be USD 100000 when you travel out of country. If you are planning to trek in mountain its chance to get altitude (AMS) problem so you need helicopter rescue in that case. That is why all the traveler must have insurance that cover helicopter evacuation service even in mountain. There are many insurance company around the world which you can find very easily in Google. You can choose the best insurance company who provide helicopter service in mountain if you have any accident, injuries, AMS and other health problem.