Motorway lane allocation sign
A blue sign with a diagram showing the left lane exiting and two others continuing, and the following text.
Left lane destinations: The MIDLANDS; The SOUTH WEST; M5.
Right-hand two lanes destinations: London; Bristol (M32); M4.
Junction number: 20.
A long climb uphill brings us to Almondsbury Interchange, the UK's first four-way motorway junction and its first four-level motorway junction, where we find the M5.