Gravelly Hill - The most complex 'pasta' intersection on the planet

The "pasta" intersection seen from above.

Inaugurated on May 24, 1972, Gravelly Hill is famous for its unique shape resembling a plate of pasta. This is the first straight intersection without traffic lights or roundabouts in the UK. Gravelly Hill is an important part of the Midland Links project connecting the M1 (London - Yorkshire), M5 (Birmingham - South Wales) and M6 (Birmingham - Preston) motorways. These routes are the three main branches of the UK National Highway Network.

In 1958, the Ministry of Transport appointed Sir Owen Williams and Partners as a consulting engineer to explore the plan to connect the three routes. The engineering team decided that the straight line would better connect the main residential areas instead of the longer ring road to avoid the high-construction area. To limit the amount and cost of demolition required to create a straight line, they decided to use existing routes through canals, rivers and bridges. The project includes 69 km of highway passing through suburbs, 37 km of highway passing through urban areas and 17 intersections. The engineering team in charge of the project also built a 21.3 km viaduct spanning the Tame River. At the same time, they also created the longest continuous viaduct in the UK with a length of 5.6 km between Gravelly Hill and Castle Bromwich.

Construction of the intersection took four years from 1968 and opened in 1972. Construction costs amounted to 12 million USD at that time. This is an extremely complex intersection with many traffic lanes and consists of 5 floors. Engineers used a total of 13,000 tons of steel and 134,000 cubic meters of concrete. The intersection has 559 supporting concrete columns, of which the highest column is 24 m.

When inaugurated, the average traffic through Gravelly Hill intersection was 40,000 vehicles/day. The number increased to 140,000 vehicles in 2002 and over 210,000 vehicles in 2012. According to the National Highways Commission, the construction is designed to last 120 years.