The fact that Cornwall sticks out into the southwest so far makes it that it does not only have the most westerly point of Great Britain, but also the most southernly one, the tip of the Lizard Peninsula, which is called Lizard Point. Here there is not so much ballyhoo about it like at Land's End, which is quite enjoyable.
The both other extremes of Great Britain are, by the way, Ness Point in Lowestoft, Suffolk (most easterly point) and Dunnet Head on the north coast of Scotland (most northernly point).