Smørrebrød is the traditional Danish open sandwich which is normally eaten for lunch. They have a rye bread base, usually spread with butter, then a variety of toppings can be added.
Common ingredients include various cold meats, pickled, curried or smoked fish, caviar, boiled egg, tomato, cucumber, sweet pickle, horse radish, pickled red cabbage and mayonnaise.
You will find many stores in Copenhagen that are dedicated to making fresh Smørrebrod every day using a wide variety of toppings. There are literally hundreds of different combinations of topping.
If you ever visit Copenhagen, you certainly owe it to yourself to try some Smørrebrød!