[1][3][4] The E30 uses primary routes and motorways across the UK and is approximately 355 miles (571 km) between Felixstowe in East Anglia and Fishguard Harbour, Goodwick, in Wales.

[5] On mainland Europe, the E30 terminates at Hoek-van-Holland where a ferry is required to cross the North Sea to Felixstowe, United Kingdom.

These include: Chepstow is home to several scientific research centres, for example, CreoMedical, a firm which develops medical technologies for hospitals across the UK.

ABP maintains a presence at some of these destinations (not Llanelli, additionally at Barry), and handles over 12 million tonnes of freight each year, contributing over £1.5 billion to the economy.

[15] In November 2016, Brexit supporter David Rowlands AM (UKIP) argued that the Welsh Government should use trans-European Highways Access funds to maintain the M4 following the UK's departure from the EU.

He justified his viewpoint by claiming that a large proportion of all Irish exports, both to the UK and the EU, pass along this route.