A death march is when a group of people are forced to walk a long way without breaks or food, usually in very bad conditions. Imagine going on a really, really long hike and not being able to stop at all, even if you are tired or hungry. It can be very dangerous and sometimes people can even die from it, which is why it's called a death march. This is usually caused by wars or other situations where people are forced to move quickly and away from their homes. It's very sad and scary and we should always try to prevent it from happening.