Box junctions - those yellow grids at road intersections - were first used in London in 1967. The idea was to keep junctions clear. The execution depends entirely on British politeness and rule-following.
The breathalyser test was introduced in the UK in 1967. The legal limit was set at 80mg per 100ml of blood, where it remains today. Some numbers stick around for good reasons.
Seat belts became compulsory for front seat passengers in 1983, and rear passengers in 1991. Britain was relatively late to mandatory seat belt laws. Better late than airborne, though.
Pelican crossings were introduced in 1969. The name comes from PEdestrian LIght CONtrolled crossing. Someone in the Department of Transport was quite pleased with that acronym.