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Bæjarins Beztu Pylsur10
Why locals love it?
Well.. I lied. It's not really a restaurant, but a hot dog stand. The British newspaper Guardian said them to be the best hot dog stand in Europe! The line can be long, but its still worth it.
Why you should visit it
If you will not visit this yourself, some Icelander will drag you there anyway. Could be the best hot dogs you will ever try.
Order like a local and yell proudly "eina með öllu" (e. one with everything) when it's your turn.