Rhos-on-Sea (Welsh: Llandrillo-yn-Rhos; sometimes shortened to Rhos or Llandrillo) is a seaside resort in North Wales. It is a mile to the north but effectively a suburb of Colwyn Bay, and lies on the north coast of Wales at Latitude: 53� 18'N Longitude: 03� 44'W
In Rhos is the sixth century St Trillo's Chapel, (Llandrillo yn Rhos) which was the mother church of a large parish which included places as far apart as Eglwysbach and Eglwys Rhos (Llan Rhos). The chapel is on the site of a pre-Christian holy well, of which there are many in Wales; the altar is built directly over the well.
On the slopes of Bryn Euryn, are the ruins of Llys Euryn, the court of Ednyfed Fychan, seneschal to Llywelyn the Great. In a charter of 1230 Llywelyn sanctioned the purchase of the land between Bryn Euryn and the sea shore known as Rhos Fynach, in the township of Dinerth, the "fort of the bear". Rights to the fishing weir were traditionally granted to the Cistercian Abbey of Conwy at their outpost of Rhos Fynach by Llywelyn. Trial excavation of the weir site in 1993 recorded two phases of construction, carbon 14-dated between 1500 � 1660. Aberconwy Abbey and Rhos Fynach passed to secular owners after the Dissolution of the Monasteries; Rhos Fynach and its weir eventually came into the hands of Robert Dudley, Earl of Leicester. The weir continued to provide livelihood through the 19th century: during a single night in 1850, 35,000 herring were caught, and 10 tons of mackerel were removed in one tide as late as 1907. Rhos Fynach, now on the Rhos Promenade near St Trillo's Chapel, was the seat of the Parry-Evans from the 16th century to the late 19th. The house is now a pub & restaurant.
Perhaps Rhos-on-Sea's greatest claim to fame is that, according to legend, Madoc ap Owain Gwynedd, a Welsh prince, sailed from here in 1170 and discovered America, over three hundred years before Christopher Columbus's famous voyage in 1492. This event is recorded by a plaque on one of the properties on the sea-front.
Rhos-on-Sea also has a puppet theatre.