This junction is spread across 30 acres and has 18 routes which include slip roads ( 4km or 2.5 miles). It has a total of 559 concrete columns and passes over two railway lines, three canals, and two rivers
The construction work started in 1968 and was completed in May 1972 and till date its considered as one of the most complicated road network in world.
Check out the construction video of Gravelly Hill – Spaghetti Junction UK