M4 motorway not signed, European route E30 includes most of the M4. The M4 has two sections of smart motorway. The one between junctions 19 (M32) and 20 (M5) north of Bristol has variable speed limits and a part-time hard-shoulder. Completion was in summer 2014. The section between junctions 24 and 29 in Newport has variable speed limits. In 2010 it was announced that a smart motorway would be constructed between junctions 3 and 12, with work starting in Autumn 2018. This will be the longest smart motorway scheme in the United Kingdom, with a length of 51km (32 miles). Work is
A4/M4 (Sydney) Cahill Expressway, Western Distributor and Bradfield Highway in . In 2013, as part of the statewide alpha numeric route conversion, the Metroad 4 was replaced by M4 for the motorway and A4 for the non-motorway section. A4/M4 (Sydney) The A4 and M4 is an arterial route in Sydney, New South Wales, Australia. It connects the inner-west of Sydney with the outer western suburbs. It used to be Metroad 4, which was a Metroad in Sydney. The A4/M4 mostly follows what was previously National Route 32 from the Western Distributor in the CBD, west to the Great Western Highway (Route 32)