Ar hyn o bryd, dim ond 2.5% o ffyrdd Cymru sydd â therfyn cyflymder o 20mya, ond o'r flwyddyn nesaf disgwylir i hyn gynyddu i tua 35%, gan helpu i greu ffyrdd a chymunedau mwy diogel ledled Cymru.
Currently, just 2.5% of Welsh roads have a speed limit of 20mph, but from next year this is expected to increase to approximately 35%, helping to create safer roads and communities across Wales.