Where to eat it: Iceland, New York City, Chicago
There are three cities where grabbing a hot dog on the street is a must.
In New York, hot dog carts are found on practically every street corner and hungry pedestrians will eat it with spicy brown mustard, onion relish and sauerkraut.
In Reykjavik, the hot dog is made with mostly lamb meat and are topped with ketchup, mustard, raw white onions or crispy fried onions and mayonnaise with chopped pickles sauce.
In Chicago, don't even think of putting ketchup on your dog. Chicago style "forbids" it. Instead, yellow mustard, chopped onions and sweet pickle relish are permitted.