This report provides information on vehicle speeds on Welsh motorways, that is the A48(M), M4 and the M48 for April to June 2016.
Mae’r adroddiad hon yn darparu gwybodaeth am gyflymder cerbydau ar draffyrdd Cymru, sef yr A48(M), yr M4 a’r M48 ar gyfer Ebrill i Mehefin 2016.