The regularly-scheduled airline flight between Westray and Papa Westray in the Orkneys is, at least according to Guinness, the shortest of its kind in the world. Flown by a Loganair Britten-Norman Islander (and being exactly the sort of little commuter hop the islander was intended for, hence the name), you can see why there's currently a project investigating the possibility of electric propulsion for these planes.
While on Papa Westray, you can visit the Knap of Howar, which is supposedly the oldest standing stone dwelling in northern Europe, at some five thousand years old.
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