Spaghetti source - Telegraph It is 40 years since the Gravelly Hill interchange on the M6 opened to motorists. And if that does not sound like much of an anniversary to mark, it is better known as Spaghetti Junction, the ultimate manifestation of the motor car's triumph over the environment. For Roy Smith, a journalist on the Birmingham Evening Mail, who coined the colloquialism, it represents immortality in concrete form: his term has been applied to dozens of similarly convoluted motorway interchanges around the world. Yet despite the extraordinary engineering feat of joining up 18 routes with 2.5 miles of slip-roads across five different levels propped up by 559 columns, the designers have earned nothing but eternal opprobrium. Beneath its frenzy, however, narrow boats still wend their way along the Tame Canal, built in 1844, without a nickname.