Hornets are often (although wrongly) thought to be very aggressive and dangerous, and are much feared by some people. Hornets can actually be seen to slowly crawl backwards and eventually flee, rather than attacking, when approaching them. This can make it hard to remove hornets from indoors, if they happen to come in through an open window or door. Some folk beliefs have it that three stings from the European hornet can kill an adult human, and that seven can kill a horse. While impressive due to their size, European hornets are in fact much less aggressive than some of their smaller relatives (notably the yellowjackets Vespula germanica and Vespula vulgaris), and their sting isn't more dangerous. Unwarranted fear has often led to the destruction of nests, and the species is locally threatened. It benefits from legal protection in some countries, notably Germany.
Hornets are not harmless, however. They have a painful sting and can cause anaphylactic shock to persons with an allergy to wasp venom, a condition which can be fatal. While not aggressive when encountered far from the nest, workers will vigorously defend the nest if provoked.