The A55 is the main north Wales coastal route and is part of Euroroute E22 Trans-European Transport Network (TEN-T).
Yr A55 yw’r prif lwybr ar hyd arfordir y gogledd ac mae’n rhan o Rwydwaith Trafnidiaeth Traws-Ewropeaidd (TEN-T) Euroroute E22.