Speed limits in built-up areas will be reduced from 30mph to 20mph in Wales on Sunday - a UK first that has caused controversy with some drivers.
The law will change the speed limit on about 35% of Welsh roads where lamp-posts are no more than 200 yards (183m) apart.
The Welsh government said the £32.5m cost to rollout the new nationwide speed limit was “outweighed” by reduced impact on the NHS and emergency services, which one study said could save £92m a year.
But a Welsh government-commissioned consultation found more were against the speed limit than in support of it.
One of the Labour-led government’s own documents said longer journeys could cause a “substantial” economic disadvantage.
Its “central estimate” was an economic hit of £4.5bn over 30 years, although ministers acknowledged there was “significant uncertainty” over the figure and “active professional debate” about how it was calculated.
The UK government’s House of Commons leader, Penny Mordaunt, called the new 20mph default limit “insane” and said it was “punishing” motorists.
The Welsh Conservatives said they were in favour of a 20mph limit outside schools, hospitals and care homes - but called the blanket rollout “disastrous, frankly ludicrous and a war on motorists”.
Welsh ministers said impact on journey time would be “small”, with drivers taking less than one minute extra on average per trip.
Good for Wales …
If lives are saved then drivers will have to learn to live with lower speeds …
Of the 1,014 people killed or severely hurt on Welsh roads in 2022, more than 40% (421) were hit on a 30mph stretch of road.
Road safety campaigners Brake said a person’s risk of dying if they are hit by a car travelling at 30mph is five times greater than if the car was travelling at 20mph.
Because it will be the new national speed limit, 20mph signs will no longer be needed on those roads - except when the limit changes.
So, be warned:
Will police enforce the 20mph speed limit in Wales?
From Sunday, if you’re pulled over doing more than 20mph in a built-up area in Wales you could, in theory, be fined a minimum £100 and get three penalty points.
Police say the response will be proportionate and reasonable while drivers get used to the change.
They said the focus for the first 12 months would be on education, with officers given a level of discretion.