Whether electric or petrol, diesel or gas, the units for measuring speed have modernised across the world (Letters, 31 July). Could this be the time for Britain to embrace change and start measuring your miles in kilometres? This would make things so much easier for the Irish, Germans, French, Italians, Spanish, Dutch, Swedish, Danish, Polish, Norwegians etc who love to visit your country in their cars – cars that have speed dial displays only in kilometres per hour. Sign-posting speed limits in miles per hour is meaningless to us. We have to multiply our speed (in km/h) by five and divide by eight while driving to convert. A big problem if you are travelling from the Republic of Ireland across the land border into Northern Ireland. Fear not, United Kingdom, it’s not the slippery slope, a kilometre will always be a million miles away from a euro.

Alison Hackett

Dun Laoghaire, County Dublin

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