This is an area of open land on the Isle of Gods which, although it occupies some of the most valuable building land in the city of Ankh-Morpork, will never be built on as long as there is law and statute requiring every able-bodied male to be a proficient archer. The time-hallowed custom is that archery practice is sanctioned here - no doubt because any overshoots or wild misses will end up falling in the river where they can do little damage, and may even be retrieved by somebody wearing old shoes who is willing to run quickly. Walkers on the nearby By-Your-Leave Walk are advised they do so expresssly at their own risk, however.
Although the law requiring all able-bodied men to be proficient archers is these days honoured in the breach, tradition and common law requires land be set aside for them to practice on. These days, the Butts is used for training purposes by the Watch, the Assassins' Guild, and possibly by the Regiments. There is still room for informal civilian use, however, and the archery club that once reluctantly accepted Ossie Brunt as a member practices here. As indeed did Ossie.
The Butts are approached down a street which, with that impish Ankh-Morporkian sense of humour, is commonly spelt Butt's Treat. Whether this is a sideways reference to the gender preferences of those who attend the Blue Cat Club and related venues for gentlemen of more sophisticated tastes is not known. But given the robust sense of humour of the citizens...
The mis-spelling of Butt Street suggests the equally mischievous sense of humour of those Mancunians, confronted with their town's gay nightlife area being based on Canal Street. And who insist on stealing or removing the "C" and the "S" from the street sign. A-M's "Soho" of disreputable night clubs and strip joints begins on nearby Brewer Street, after all... there is even a "So-So Street" and a Wardour Street (also exists in London's Soho) marked on the Mapp.