Generally: Denmark is a very safe country, with almost no risk of natural disasters or animal attacks. There is one poisonous, but rare and non-aggressive, snake, the European viper (Hugorm), in some heathlands and a stinging, bottom-dwelling fish called "Fjæsing", known as Greater Weever (Trachinus draco) in English. Its sting is painful, but not generally lethal. It is strong enough, however, to be lethal to children and the elderly, so medical treatment is always encouraged. Red stinging jellyfish sometimes infest bathing waters in great numbers. Their sting can be painful but has no adverse effects on humans. They are dish-sized, easy to spot and avoid. As in the rest of Europe and the world at large, borrelia carrying ticks have also been on the rise in Denmark. Always check your body for attaching ticks, when you have been in the wild, especially when legs and arms are bare and the vegetation high. If they are removed quickly, no disease will be transmitted. If the infection does occur, a red ring will occur around the bite, and you should seek medical assistance as soon as possible.

Compared to most other countries, crime and traffic are only minor risks, and the most serious crime visitors are likely to encounter is non-violent pickpocketing.

On foot: In cities, Danes drive by the rules, and they have every expectation that pedestrians do the same. Therefore, it is important to obey Walk/Do not Walk signals and avoid jaywalking in cities, simply because cars will not slow down since you are not supposed to be there. Traffic signals are obeyed around the clock, so do not get surprised to see law-abiding Danes, in the dead of night with not a single vehicle or bicycle in sight, patiently waiting for green light. You are supposed to do the same. Also, take good notice of the dedicated bike lanes when crossing any street to avoid dangerous situations as bikers tend to ride fast and have right of way on these lanes.

On the beach: Do not bathe alone. Do not get too far away from land. Swim along the coast rather than away from it. In some areas, the undertow is a danger, and kills a number of tourists every year, but will mostly be signed at the beach. On many beaches, flags indicate water quality. A blue flag means excellent water quality, green flag means good water quality, red flag means that bathing is not advised. A sign with the text "Badning forbudt" means that bathing is forbidden. Obey these signs, as it often means that the water is polluted with poisonous algae, bacteria, or chemicals, or that there is a dangerous undertow. 

In an emergency dial 112 (medical help/fire brigade/police). This is toll-free and will work even from cell phones even if they have no SIM card. For the police in not-emergencies call 114.