This is the original "spaghetti junction": the one that inspired the term. Otherwise known as Gravelly Hill Interchange, or junction 6 on the M6 (to it's friends), the junction in Birmingham was opened in 1972 involves five levels, eighteen roads, three canals, two rivers and two railways. In it's first year it carried an average of 40,000 vehicles per day, and today it averages over 200,000 - it is estimated that 2 billion cars have used it in the last 40 years. Just saying.
The term "Spaghetti Junction" was coined in 1965 by journalists from the Birmingham Evening Mail. Reporter Roy Smith described plans for the then unbuilt junction as a "cross between a plate of spaghetti and an unsuccessful attempt at a Staffordshire knot", and a sub-editor captioned the article "Spaghetti Junction".