John o'Groats is a small village on the far north coast of mainland Scotland, famous as the traditional road-end opposite Land's End. The signpost is tourist theatre, and the village itself is modest, but the surrounding Caithness coast gives the place more bite than the souvenir shops suggest.
The best reason to come is the walk or drive to Duncansby Head and the Duncansby Stacks. Sea cliffs, birds, rough water, and views toward Orkney do the real work here. On a clear day the islands sit across the Pentland Firth; in bad weather the place feels properly exposed.
John o'Groats is a good spare day if you are already on the North Coast 500 or based around Wick or Thurso. It is not the northernmost point of Britain - that is Dunnet Head - but it has the myth, the road-end ritual, and enough coast nearby to justify the stop.