Mithering Heights begins at Brookless Lane opposite the junction with Small-But-Delicious-Fishes Avenue. It has a Hubwards offshoot leading down to the the Least Gate by Barrow Ninny (*C2), budding off from Pallant Street and, as it approaches the City, takes in an intersection with Spa Lane and Tump Lane, finally meeting Brookless Lane. its importance in the other direction is that this is the beginnings of the widdershins (anti-clockwise) spiral road to the top of the Tump, eventually becoming the Old Tump Hill Walk* (begins C2). At its nearest point to the City Wall, a side-street buds off to Endless Street and the lesser thoroughfare of Garstairs*(A3). Garstairs houses riding stables offering the usual range of equestrian services "to the sons and daughters of gentlefolk".
The exact point on the City Map where Mithering Heights becomes the Old Tump Hill Walk is not clearly defined. A logical point might be at the Old Castle pub (*C2) where Mithering Heights and the spur to the Least Gate meet the spiralling roads up the Tump proper. It is noted in The Compleat Ankh-Morpork that the Old Castle is a pub where clacksmen and staff from the Grand Trunk choose to drink. There is therefore a risk of being hit, or at least bamboozled, by flying clacksman jargon. Commodity and currency speculators also tend to drink here in a bid to be first with incoming news, as does the Business and Stock Exchange section of the Ankh-Morpork Times. Casual drinkers therefore have good reason to avoid the place.
To mither is one of those loan-words Northern dialects of English (including Scots) acquired from Scandinavian languages. Still freely heard in Lancashire or Yorkshire, the verb means to pester, aggressively solicit, to whine, whinge and generally be annoying. It is often used in the context of a parent reproving a child for demanding and persisting in making demands, often in a whiny or whingy way, despite frequent and heated rebuttals from the parents.
For instance: Will you stop mithering or I'll give you a right clip round the ear! I've already said no!
The other association is too obvious and suggests a tale of passion and forbidden love, with a Discworld twist, marketed by Velmans and Jones, publishers...