A temporary replacement for the flyover.
Work started on the Conwy crossing in November 1986. Construction was undertaken by the Costain Tarmac joint venture. The work was supervised for the Welsh Office by Travers Morgan and Partners, Consulting Engineers, who were in association with Christiani and Nielsen A/S. The tunnel forms part of the A55 North Wales coast road between Glan Conwy and Conwy Morfa, a total length of about 6 kilometres. From a junction at Glan Conwy, the route connects with a link road to Llandudno Junction, before passing under the causeway which carries the Chester to Holyhead Railway and the existing A55.
Original Index No. G0071.