Gwaith hanfodol ar danbont Kneeshaw Lupton yw'r unig waith wedi'i gynllunio sydd wedi arwain at gau lonydd ar yr A55 rhwng Cyffordd 11 ym Mangor a'r ffin â Lloegr ers mis Ebrill 2017.
Essential work to the Kneeshaw Lupton underbridge will have resulted in the only planned daytime lane closures on the A55 from J11 Bangor to the English border since April 2017.