The B375 runs east of Chertsey, parallel to the M3.
Since it gets used as the back road from M25 J11 to Terminal 4 at Heathrow, the B375 can be very congested at times and with an AADT of 36,939 (2006), the B375's crossing of the Thames at Chertsey Bridge is one of the busiest B roads in Britain.
At the Chertsey end there are two branches, with the original route going through the town centre to finish on the A320, while the other (the pre-bypass A320) heads south to finish on the A317 near Chertsey railway station.
After a brief multiplex with the B376 near Shepperton the current eastern end of the B375 is on the A244 at Halliford. However, it originally continued east along now-unclassified roads along the left bank of the Thames to end on the A308 at Hampton.
Original Author(s): Mistral