M4 motorway

M4 motorway (eastern end)
M4 motorway
Route information
	Part of E30
Length	191.9 mi (308.8 km)
Existed	1961 – present
History	Constructed 1961–96
Major junctions
From	Chiswick; 51°29′23″N 0°16′41″W / 51.4897°N 0.2781°W
	; M25 motorway; ; A308(M) motorway; ; A404(M) motorway; ; A329(M) motorway; ; M32 motorway; ; M5 motorway; ; M48 motorway; ; M49 motorway; ; M48 motorway; ; A48(M) motorway
To	Pont Abraham services; 51°44′42″N 4°03′54″W / 51.7451°N 4.0651°W
Location
Primary; destinations	London; Heathrow ; Slough; Maidenhead; Reading; Bracknell; Wokingham; Newbury; Swindon; Chippenham; Bristol; Newport; Cardiff; Bridgend; Port Talbot; Neath; Swansea; Llanelli
Road network
	Roads in the United Kingdom; Motorways; A and B road zones;