Llanddulas is situated near the mouth of the river Dulas in Conwy county, North Wales. It is bordered by Bryn Dulas to the south east, Penmaen Rhos to the west, Abergele to the east and the Irish Sea to the north. Nearby towns and villages include Colwyn Bay, Old Colwyn, Llandudno, Rhyl, Pensarn, Rhyd-y-Foel, Llysfaen and Towyn. The A55 expressway passes through the village.

Gwrych Castle sits nearby. Built in 1819 for Lloyd Hesketh Bamford-Hesketh, it stayed with his granddaughter Winifred's family for several years until it was sold to Mr Robert Rennie in 1946. From there it passed along to many different people, and attracted millions of visitors each year. The castle, which dominates a hillside near Abergele, along with its magnificent gardens, finally closed in 1985. Plans are in place to convert Gwrych into a grand hotel.

In the past Llanddulas was a notable quarrying village, quarrying limestone from Cefn-yr-Ogof. Originally the limestone would have been carried to the shore by horse and cart. A wooden jetty built in 1822 made it easier for limestone to be shipped to Liverpool, whilst the completion of the railway in 1849 offered another way to transport the stone.